Sample records for por protons pixe

Studies of particle induced X-ray emission (PIXE) have been widespread and detailed in recent years and despite the fact that most data obtained are from low energy 1-3 MeV experiments, the value of higher energy proton work with its emphasis on K X-ray emission has become more marked as time has progressed. The purpose of this review paper is to outline the history of analysis using high energy protons and to compare and contrast the results obtained with those from lower energy analysis using more firmly established analytical techniques. The work described will concentrate exclusively on proton induced processes and will attempt to outline the rationale for selecting an energy, greater than 20 and up to 70 MeV protons for initiating particles. The relative ease and accuracy of the measurements obtained will be addressed. Clearly such X-ray studies should be seen as complementing low energy work in many instances rather than competing directly with them. However, it will be demonstrated that above a Z value of approximately 20, K X-ray analysis using high energy protons is the only way to go in this type of analysis. (author)

The possibilities were studied of the practical use of the analytical PIXE method. Calibration samples were analyzed of Cu, Cd, Hg and Pb in concentrations of 50 to 500 ..mu..g/l as well as natural samples of drinking water, pond water, human blood plasma, dry waste from ground vegetation, mushrooms, pine needles, aerosols, human hair, leaves and flowers, etc. The samples were processed using precipitation, mineralization or incineration and were trapped on a membrane filter (Synpor) or on a Tatrafan ON 15 foil. Some samples were freeze-dried and compressed into pellets. A proton beam with an intensity of 10 to 70 nA was used for analysis and the proton energy was selected 2.2 MeV. For most targets an exposure of 120 s was preset and the measurement lasted at least 60 s and 600 s at the most. It was found that Synpor filters browned and became more brittle during longer exposures. The other targets did not change during analysis.

The energy of the proton beam plays an important role in the type of analysis that is intended. The need to take into account energy loss of the particles beam inside the specimen, the energy variation of the ionisation cross section for K and L lines, secondary fluorescence, and the surface topography draws the line between thin and thick target analysis. We present here the difficulties, calibrations and calculations for the ionisation cross sections needed to quantify at proton energies below one MeV. As conclusion we show with an example the necessity of reliable standards. (author)

Since 1987 the CSIRO Div. of Exploration Geoscience has carried out a program of proton-microprobe (PIXE) analysis aimed at using trace-element data on indicator minerals to discriminate between those from diamondiferous and barren source rocks. The results have provided both important new tools for the exploration industry, and significant new information on the conditions and processes of diamond growth. Cr-pyrope garnet has been used as Ni thermometer while chromites, in partcular their Zn content, has allowed correlation of chromite composition with temperature. The two techniques described provide a significant increase in exploration efficiency, through early recognition and rejection of barren targets and concentration of resources on more promising targets. They also provide direct cost savings in evaluation of ore bodies once they are found. It is estimated that evaluation of a prospect by conventional bulk testing is expensive ($100-500K) and time-consuming; an evaluation by PIXE methods is done quickly for a tiny fraction of that cost. 1 refs., 4 figs

We intend to develop a system that can extract a proton beam into air for a qualitative, and quantitative PIXE analysis up to ppm(percent per million) composition. When such an R and D is accomplished, first it is possible to get equipped with a system for PIXE and PIGmE, second, it is possible to contribute to an academic progress by the study for physical properties of matter through an nuclear science methods when the comparison between the measurement and the calculated quantities, and third, it is possible to contribute to a multi-disciplinary researches by the measurements of the samples for which it is hard to get the SRM for the samples. We intend to develop methods to measure the beam current for an air-borne proton beam, and to minimize the energy and current loss of the beam. We intend to acquire a set of PIXE data for rare-earth metals and transient metals, to form a basic database for the analysis for various samples for which it is hard to get the SRM. Developed PIXE beamline can extract the beam diameter up to 5mm, and beam intensity in the range 0.5nA to 10nA variable. sustaining the vacuum better than 10{sup -6} mtorr. Necessary detection system and methodology are complete. As the application of the present research achievements, we studied the analysis of aerosol composition, the appraisal of the cultural heritages, and a feasibility study for a proton beam writing. It is expected to become possible to analyse the compositions of the gems, the elemental compositions of the food, the discrimination of the traditional ink and the modern ink on the documents, the evaluation of the documents by the analysis of the elemental composition of the stamps, The analysis of the paper with respect to the date and the quality, the analysis of the color, and the core bored samples

Caatinger (Mimosa acutistipula Benth), which has been a popular wood among the people in north east part of Brazil, was analyzed using PIXE (proton induced X-ray emission). The wood sample was divided into three parts, center, inner and outer side of the wood. Using the wood slice of each part, Na, Mg, Al, Si, P, S, Cl, K, Ca, Ti, Mn, Fe, Cu, Zn, As, Se, Br, Rb, Sr, Y, Ru and Pb were detected. When the wood slices were decomposed with nitric acid, Co and Ni were able to be determined. Two samples, non-destructive and chemically treated sample, of heartwood and sapwood showed the similar concentration of the elements. There was a discrete change of the accumulated elements between heartwood and sapwood. Most of the elements detected tended to be concentrated at sapwood, whereas Ca, Cu and Sr were concentrated at heartwood. At center part, especially, Na, Mg, Fe and Sr were accumulated. Since most of the heartwood and sapwood is dead, discrete change of the element concentration suggests some element movement across the annual ring at heartwood formation. (author)

Particle-induced X-ray emission (PIXE) analysis is usually performed using proton beams with energies in the range 2∼3 MeV because at these energies, the detection limit is low. The detection limit of PIXE analysis depends on the X-ray production cross-section, the continuous background of the PIXE spectrum and the experimental parameters such as the beam currents and the solid angle and detector efficiency of X-ray detector. Though the continuous background increases as the projectile energy increases, the cross-section of the X-ray increases as well. Therefore, the detection limit of high energy protonPIXE is not expected to increase significantly. We calculated the cross sections of continuous X-rays produced in several bremsstrahlung processes and estimated the detection limit of a 20 MeV protonPIXE analysis by modelling the Compton tail of the γ-rays produced in the nuclear reactions, and the escape effect on the secondary electron bremsstrahlung. We found that the Compton tail does not affect the detection limit when a thin X-ray detector is used, but the secondary electron bremsstrahlung escape effect does have an impact. We also confirmed that the detection limit of the PIXE analysis, when used with 4 μm polyethylene backing film and an integrated beam current of 1 μC, is 0.4∼2.0 ppm for proton energies in the range 10∼30 MeV and elements with Z = 16-90. This result demonstrates the usefulness of several 10 MeV cyclotrons for performing PIXE analysis. Cyclotrons with these properties are currently installed in positron emission tomography (PET) centers.

The state of the proton induced X-ray emission (PIXE) work at Lucas Heights is reported together with a full description of the experimental arrangement and its use for analysis of trace elements (Z >or= 14). The fundamentals of PIXE are examined in detail with a view to understanding not only the background continuum but also the X-ray production mechanisms. Quantitative predictions for the number of X-rays detected after proton bombardment of the target have been made and these compare well with experiments

At the present time, the microanalysis technique PIXE is accepted by the scientific community as one of the basic techniques used in the study of airborne particle matter, due to the multiple qualities that this offers for the study of this type of pollutants. The nuclear techniques have important applications in the study and technology of solid materials, archaeology and biomedical studies, and particularly in the study of the particles suspended in the air where the PIXE technique is more used because provides reliable results for the identification and quantification of chemical elements from the aluminum until the uranium, including all the metallic elements. Among the main reasons that have motivated the study of the particles suspended in the air is the fact that these cause effects in the human health. At the moment, the sanitary problems associated to the particles are a reason of great concern in many countries where in very populated cities the total of particles in suspension often surpasses the limits settled down by the World Organization of the Health. (Author)

A multielemental analysis to determine the trace metal content of generic and name-brand aspirins and name-brand lipsticks was done via proton induced x-ray (PIXE) measurements. The Hope College PIXE system is described as well as the target preparation methods. The trace metal content of twelve brands of aspirin and aspirin substitutes and fourteen brands of lipstick are reported. Detection limits for most elements are in the range of 100 parts per billion (ppb) to 10 parts per million

In this work the results of the analysis are presented, using the PIXE technique (Proton Induced X-ray Emission), in soil samples of the El Bordo, Vetagrande, Zacatecas, before and after subjecting them to a lixiviation process for the recovering of gold, silver and mercury. This community is part of the mining region nearer to the Zacatecas city municipality, region in which the mining exploitation dates from the colonial time. During almost 350 years the 'yard benefit' method was used or amalgamation with mercury, process that besides having used big quantities of mercury, generated a great quantity of mineral waste calls 'mine wetlands', those that were accumulating, crawled by the rains, toward the streams that end in the prey 'The Pedernalillo'. The dispersion of wetlands them it has extended from the prey until the communities of Tacoaleche, Zoquite, Lampotal and El Bordo, embracing an approximate area of 16 x 2 Km{sup 2} and forming with the course of the time an accumulated of several millions of tons. In order to determining if the process of recovery of gold, silver and mercury make soluble to other contained metals in these wastes, samples were gathered in an area of 600 m{sup 2} in the community of The Border, Vetagrande, Zacatecas. Half of the samples were subjected to the lixiviation process in a local metal recovery plant and the other part was analyzed without processing. The analysis of both types of samples by means of the PIXE was carried out in the University of Arizona in Tucson. (Author)

The technical and methodological prerequisites are summed up for the use of the PIXE method with an external proton beam. The method is suitable for the preliminary analysis of unknown samples prior to the choice of the best suited analytical method, for the nondestructive analysis of rare samples such as unique works of art, of small amounts of materials which are difficult to access, etc., as well as for calibration and comparing analyses. As for the operators the application of the PIXE method with external proton beam assumes the availability of accelerator operating time, minimization of the length of exposure of the targets, optimization of parameters of the exciting beam and automation of the whole process. Attention is also devoted to technical provisions and organization of laboratory work. The design is described of an analytical unit using the PIXE method with external proton beam, and it is stated that the Van de Graaff accelerator at the Institute of Nuclear Physics in Rez near Prague could be used for the purpose. (Z.M.). 6 refs

Proton Induced X-ray Emission Technique (PIXE) has been used in analysing Gold standards of 22, 20, 18, and 14 karats with a proton beam of energy 3.3 MeV at the newly commissioned Folded Tandem Ion Accelerator (FOTIA). Well resolved Au and Ag X-rays were detected at a current of 3 nA. Percentage values of gold and silver were calculated and were checked with those obtained by Energy Dispersive X-ray Fluorescence Method and were found to be in agreement with the certified values as well as those obtained by XRF. (author)

Metallic nanoparticles (MNP) are able to release localized X-ray when activated with high energy proton beam by particle induced X-ray emissions (PIXE) effect. The exploitation of this phenomenon in the therapeutic irradiation of tumors has been investigated. PIXE-based X-ray emission directed at CT-26 tumor cells in vitro, when administered with either gold (average diameter, 2 nm and 13 nm) or iron (average diameter, 14 nm) nanoparticles, increased with MNP solution concentration over the range of 0.1-2 mg/mL. With irradiation by 45-MeV proton therapy (PT) beam, higher concentrations had a decreased cell survival fraction. An in vivo study with tumor regression assay demonstrated significant tumor dose enhancement, thought to be result of the PIXE effect when compared to conventional PT without MNP using a 45 MeV proton beam (p<0.01). These effects were observed for gold and iron MNP, injected in doses of 100-300mg/kg body weight into CT-26 mouse tumor models via tail vein. A therapeutic effective MNP concentration range, in vivo,was estimated at 30-79 μg/g tissue for both gold and iron nanoparticles. The tumor dose enhancement may compensate for an increase in entrance dose associated with conventional PT when treating large, solid tumors with a spread out Bragg peak (SOBP) technique. The use of combined high energy Bragg peak PT with PIXE generated by MNP, or PIXE alone may result in new treatment options for infiltrative metastatic tumors and other diffuse inflammatory diseases

Variations in linear density along a given hair can cause changes in X-ray intensity which do not reflect elemental concentration changes. Hairs from different subjects vary by a factor approx. 5 in linear density, so that very different X-ray intensities need not necessarily reflect different concentrations. We investigate the usefulness of the backscattered proton intensity as a means of determining the mass undergoing PIXE analysis. Specimen damage can be avoided in the BS measurement via low currents without loss of statistics. A correlation is found between BS intensity and mass, but a laser diffraction measurement of the hair diameter provides an equally satisfactory mass determination. (orig.)

Complete text of publication follows. Besides the ongoing applications in archeometry, geology, material science and atmospheric aerosol study, in recent years the IBA Group in Debrecen has joined several biological and biomedical research projects. Such studies require the knowledge of accurate quantitative elemental concentrations and distributions in organic, inhomogeneous thin samples on a microscopic scale. In most cases, to carry out quantitative investigations on biomedical samples down to the cell level, the combination of proton induced X-ray emission (PIXE), Rutherford backscattering (RBS) spectrometry and scanning transmission ion microscopy (STIM) analytical methods are used simultaneously. STIM provides information on the density and structure of the sample, PIXE measures the concentration of the inorganic major and trace elements, and finally RBS serves to characterize the organic matrix, to determine the beam dose, and sometimes the sample thickness. The drawback of this combined method is that to evaluate the RBS data the hydrogen to carbon ratio in the sample must be known. The setup developed at the Debrecen microprobe facility [1] is based on the combined application of on-axis STIM and simultaneous PIXE-PIXE analytical techniques. In the PIXE-PIXE method the sample matrix is determined directly by measuring X-rays from all elements in the sample including the light elements such as carbon and oxygen, using two Si(Li) X-ray detectors. In this arrangement an ultra thin windowed Si(Li) X-ray detector serves to characterize the matrix by measuring low energy X-ray lines (0.2-9 keV) while a large area Be-windowed detector is used to detect the medium and high energy X-ray lines (>4 keV). In this way elements with atomic number higher than 5 can be detected simultaneously, reducing both radiation damage of the sample and measurement time. In addition, the knowledge of the hydrogen content of the sample is not needed, since it influences the

Traditional methods for X-ray imaging using PIXE and the Proton Microprobe have used a simple gate set on an X-ray peak in a spectrum from a Si(Li) detector to provide an image of the distribution of an element. This method can produce artefacts in images, due to overlapping X-ray lines from interfering elements, charge collection tails on peaks, background variation, Si escape peaks and pileup, all of which can render images misleading or qualitative at best. To address this problem, a matrix transform method has been developed at the CSIRO which not only eliminates most artefacts, but can be implemented on-line. The method has been applied to study trace gold distribution in a complex gold bearing ore from Fiji , and more recently has been installed for direct on-line elemental imaging at the NAC in South Africa. 4 refs., 2 figs.

Traditional methods for X-ray imaging using PIXE and the Proton Microprobe have used a simple gate set on an X-ray peak in a spectrum from a Si(Li) detector to provide an image of the distribution of an element. This method can produce artefacts in images, due to overlapping X-ray lines from interfering elements, charge collection tails on peaks, background variation, Si escape peaks and pileup, all of which can render images misleading or qualitative at best. To address this problem, a matrix transform method has been developed at the CSIRO which not only eliminates most artefacts, but can be implemented on-line. The method has been applied to study trace gold distribution in a complex gold bearing ore from Fiji , and more recently has been installed for direct on-line elemental imaging at the NAC in South Africa. 4 refs., 2 figs.

The purpose of this work was to establish the conditions to analyze elements of Z>15 in powdered milk samples using the PIXE technique. Ten different commercial samples were analyzed: 2 full-cream, 3 half-cream and 5 for infant feeding. They were all purchased in Toluca City, Mexico. Thick targets were prepared and irradiated with 1.5 and 3 MeV protons beam in Mexico's Nuclear Center Tandem Van de Graff Accelerator. The obtained data were analyzed by two computers programs. Iron, the reference element was analyzed by atomic absorption spectrometry. Concentrations of the following elements: phosphorus, chlorine, potassium, calcium, chrome, iron, cobalt, nickel, copper, zinc, bromine, rubidium, molybdenum and cadmium were evaluated. The concentrations of the first four elements were usually high, whereas those of the other elements remained in some ppm. The experimental conditions set up in this work were suitable for the analysis of powdered milk and can be applied to other organic samples (Author)

Full text: PIXE is a very sensitive analytical method to determine the chemical composition of art objects, e.g. drawings, handwritings etc. A particular advantage is the possibility to analyze objects non-destructively under atmospheric pressure. Such an external beam PIXE facility is currently implemented at the Vienna Environmental Research Accelerator (VERA). The set-up allows to extract a 3 MeV proton beam of approximately 100 μm in diameter and currents in the range of a few nA's through an ultra-thin (0.1 μm) Silicon Nitride window. The characteristic x-rays emitted from the specimen are recorded with a Si(Li) and a Silicon Drift detector simultaneously to cover the widest possible Z-range of the detected elements. We have just completed an extensive period of studying beam effects on ancient paper to exclude possible damage to art objects, in particular drawings of the Renaissance that are among the most precious and rarest treasuries of graphical collections. They were created with different materials such as inks, chalks and metal points. A large collection of these fine arts objects is situated at the Albertina in Vienna. Together with scientists from the Centre de Recherche et de Restauration des Musees de France (C2RMF) in Paris, I. Reiche, A. Duval, H. Guicharnaud, from the CEREGE UMR CNRS 6635 in Aix-en-Provence, S. Merchel, from the Albertina in Vienna, E. Thobois, H. Singer, and from the Akademie der bildenden Kuenste in Vienna, M. Schreiner, we want then to analyze a few selected silverpoint drawings by Albrecht Duerer (1471-1528). (author)

The development of the PIXE method for multielemental analysis is described. A brief account is given of the physical principles and the experimental arrangements. The use of PIXE is illustrated by a number of typical applications in geology, biology, medicine and environmental research. (orig.) [de

The aim of this work is to determine the elemental composition of tree leaves using Proton-Induced X-Rays Emission (PIXE) and Atomic Absorption Spectrophotometry (AAS) methods. By PIXE Spectrometry we identified and determined the concentration of S, Cl, K, Ca, Ti, Cr, Mn, Fe, Co, Ni, Cu Zn, As, Br, Sr and by AAS method the concentration of elements: Cr, Mn, Fe, Co, Cu, Zn, Se, Cd. Pb was identified in only 2 samples from 29. For tree leave samples collected at a large distance to the polluting source the Sr concentration decreased and the Mg, Ca, Se, Zn and Fe concentrations increased. Also, we can observe a small affinity of these leaves for the environmental Pb which was detected for two samples at a small distance to polluting source. (authors)

In the framework of the COBRA project, elemental analyses of cultural heritage objects based on the particle induced X-ray emission (PIXE) are planned in a collaboration between the APAM laboratory of ENEA-Frascati and the LABEC laboratory of INFN in Florence. With this aim a 3-7 MeV pulsed proton beam, driven by the injector of the protontherapy accelerator under construction for the TOP-IMPLART project, will be used to demonstrate the feasibility of the technique with a small-footprint pulsed accelerator to Italian small and medium enterprises interested in the composition analysis of ancient artifacts. The experimental set-up for PIXE analysis on the TOP-IMPLART machine consists of a modified assembly of the vertical beam line usually dedicated to radiobiology experiments: the beam produced by the injector (RFQ + DTL, a PL7 ACCSYSHITACHI model) is bent to 90° by a magnet, is collimated by a 300 μm aperture inserted in the end nozzle and extracted into ambient pressure by an exit window consisting of a Upilex foil 7.5 μm thick. The beam is pulsed with a variable pulse duration of 20-100 μs and a repetition rate variable from 10 to 100 Hz. The X-ray detection system is based on a Ketek Silicon Drift Detector (SDD) with 7 mm2 active area and 450 μm thickness, with a thin Beryllium entrance window (8 μm). The results of the calibration of this new PIXE set-up using thick target standards and of the analysis of the preliminary measurements on pigments are presented.

Elemental analysis of ancient Indian coins viz. thirty-three punched marked coins (6 th century B.C.), fifty-nine coins belonging to Kusanas (78-250 A.D) and twenty-five coins belonging to medieval period (11 th -14 th century A.D), from India have been analysed using Proton Induced X-ray Emission (PIXE) technique. The elements namely S, Ca, Fe, Ag, Cu, Ni and Pb were detected in most of the punch-marked coins while elements namely S, Cl, K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, As and Zn were detected in most of the Kusanas coins and the S, Ca, Fe, Cu, Ag, Sn, Pb were detected in 11 th -14 th century A.D. coins. Based on the elemental analysis different hypotheses put forward in the earlier literature were examined. This is the first attempt where reasonable number of ancient coins belonging to different periods were analysed by modern non destructive multi-elemental technique such as PIXE and has put the importance of the elemental analysis of ancient Indian coins in the proper perspective

The experimental device described allows the extention of the PIXE (Particle Induced X-ray Emission) method to the analysis, by means of proton beams, of solid or liquid samples, which can not be analyzed under vacuum conditions. The homogeneity of the surfaces to be analysed and elements (in the atmosphere) which absorb X-rays must be taken into account. Liquid samples do not need special care. The results show that: at high energies, the extracted beam sensibility is of the same order of magnitude as those obtained under vacuum; at low energies, the performance under vacuum conditions is better. The particles energy losses, at the exit membrane and in the outer atmosphere, decrease the X-rays production efficiency [fr

The increase of drug counterfeits and its unconscious use has become a major cause for concern to health care practitioners and relevant stakeholders. The occurrence of counterfeit or fake drugs is perceived to be a problem encountered in both developing and underdeveloped nations where Ghana is not an exemption. The lethal implications of counterfeit/fake medications are well understood to be a major challenge to the soundness of public health systems around the world, as well as a direct threat to our individual health and well-being. Sub-standard and counterfeit/fake drugs are a widespread problem in Ghana and the need to address it is eminent. The volume of drugs that require control, from the statutory organisations like Food and Drugs Authority of Ghana (FDA) and Ghana Standard Authority (GSA) is enormous, and hence the need to explore other faster analytical techniques to help control cannot be over emphasised. According to the World Health Organization (WHO), Antibiotics are the most counterfeited drugs and Amoxicillin (C 16 H 19 N 3 O 5 S) happened to be ranked first on the list. The most used and prescribed method for drug quality control analysis is the High-Performance Liquid Chromatography (HPLC) technique which accesses the quality of drugs from its Active Principal Ingredient (API) perspective. The main focus of this study is to harness additional analytical procedure to enhance the routine monitoring of the quality of some Amoxicillin drugs in Ghana from the inorganic constituent point of view. HPLC and the physical parameter tests were carried out on the samples analysed to help validate the interpretation of the inorganic element results from the PIXE technique. Two different local brands of amoxicillin and two imported amoxicillin brands were chosen for this study. A total of 30 samples were analysed for this study including one (1) standard reference material (amoxicillin) acquired from a licenced pharmaceutical company in Ghana. Particle

The PIXE technique has been successfully applied to study crime related problems in forensic science. The experimental arrangements and various practical problems involved are discussed. Consistency and reproducibility checks are presented. The results from the gun-shot residue profiles of the associated elements about the bullet hole obtained for various firing distances showed that the sensitivity of the PIXE technique could play a vital role in forensic science in assigning the distance from the gun to the victim and identifying the type of bullet used. PIXE runs on other forensic related specimens demonstrate its usefulness in indetification and evaluation of vital parameters related to a crime. The reliability and the importance of the PIXE method in solving criminal and related problems in forensic science are discussed. (orig.)

Proton beams of diameters of 3 mm and 3 μm, were used to observe the differences in PIXE yield from pure metal targets encapsulated with PTFE, glass (macor) and nylon. The beam energy was kept constant at 700 keV. Beam currents varied from about 200 pA with the microbeam and between 1-10 nA with the macrobeam. Considerable enhancement was observed mainly with the use of PTFE, up to about a factor of 18 with the macrobeam and 306 with the microbeam. (author)

The Union College Ion-Beam Analysis Lab's 1.1 MV tandem Pelletron accelerator is used to determine the presence of heavy trace metals in Queens, NY between Astoria Park and 3.5 miles south to Gantry State Park. A PIXE analysis was performed on 0.5 g pelletized soil samples with a 2.2 MeV proton beam. The results show the presence of elements ranging from Ti to Pb with the concentration of Pb in Astoria Park (2200 +/-200 ppm) approximately ten times that of the Gantry State Park. We hypothesize that the high lead concentration at Astoria Park is due to the nearby Hell Gate Bridge, painted in 1916 with lead based paint, then sandblasted and repainted in the '90s. If the lead is from the repair of the bridge, then we should see the concentration decrease as we go further from the bridge. To test this, soil samples were collected and analyzed from seven different locations north and south of the bridge. The concentrations of lead decreased drastically within a 500 m radius and were approximately constant at greater distances. More soil samples need to be collected within the 500 m radius from bridge to identify the potential source of Pb. We will describe the experimental procedure, the PIXE analysis of soil samples, and present preliminary results on the distribution of heavy trace metals.

A simple new technique for examining single hair strands to obtain linear mass densities, longitudinal profiles and transverse distribution of each trace element is described. It is primarily based upon the PIXE technique, in combination with proton back- scattering. The three main components of this technique are: 1) An accurate way of using an interpolation method to evaluate the magnitude of the correction factor accounting for the proton energy loss and X-ray absorption in the bulk of the hair is formulated; 2) A simple method to qualitatively determine the transverse distribution of each trace element in a hair is in- troduced and proved to be effective; 3) Proton back-scattering is proved to be capable of providing an ideal linear measure of the geometric hair diameter, one of the most important parameters in quantifying the results of PIXE measurements in mass concentrations. Using the technique, a PIXE system designed and constructed for routine longitudinal scanning of single hair strands is also described. (Author)

The PIXE analysis method for the determination of elements in thick samples was investigated. The text of the present thesis is arranged under the following headings: physical fundamentals and measuring equipment, quantitative analysis of thin samples, matrix effects at the PIXE analysis of thick samples, matrix correction methods, analysis of 'infinite thick' model substances, PIXE analysis of aerosol filters. (GSCH)

Thick-target PIXE analysis insolves uncertainties arising from the calculation of thick-target X-ray production in addition to the usual PIXE uncertainties. The calculation demands knowledge of ionization cross-sections, stopping powers and photon attenuation coefficients. Information on these is reviewed critically and a computational method is used to estimate the uncertainties transmitted from this data base into results of thick-target PIXE analyses with reference to particular specimen types using beams of 2-3 MeV protons. A detailed assessment of the accuracy of thick-target PIXE is presented. (orig.)

The Proton Induced X-ray Emission (PIXE) methodology of rare earth element (REEs) analysis is discussed, including the significance of REE analysis, the principle of PIXE applied to REE, selection of characteristic X-ray for Lanthanide series elements, deconvolution of highly over lapped PIXE spectrum and minimum detection limit (MDL) of REEs. Some practical applications are presented. And the specialities of PIXE analysis to the high pure REE chemicals are discussed. (author)

We examined atmospheric aerosol samples collected in Schenectady NY for evidence of pollution. We collected aerosol samples using a nine stage cascade impactor which distributes the particulate matter by aerodynamic size onto 7.5 μm Kapton foils. We then used a 1MV electrostatic Pelletron accelerator to produce a 2.2 MeV proton beam to hit the impacted foils. X-ray intensity versus energy spectra were collected using an Amptek x-ray detector where the x-rays are produced from the proton beam interacting with the sample. This is called PIXE. The elemental composition and concentrations of the elements present in the aerosol samples were determined using a software package called GUPIX. We have found elements ranging from Al to Pb and in particular have found significant amounts of Pb and Br on some of our impacted foils, with a Br/Pb ratio of 0.6 +/- 0.2 which agrees with previous studies. This result suggests the presence of leaded aviation fuel perhaps due to the proximity of the collection site to a small airport with a significant amount of general aviation traffic. Union College.

The elemental composition of healthy and diseased teeth from 25 children has been determined using thick-target proton induced x-ray emission, (PIXE), analysis. Various dental hard tissues: enamel, dentine and cementum, and their junctions, as well as different parts of the same tissue, have been examined individually. A number of elements: Na, Mg, Al, P, S, Cl, Ca, V, Cr, Mn, Fe, Ni, Cu, Zn, Sr and Pb, has been determined in these dental tissues. The concentrations of some of the elements tend to vary considerably from tooth to tooth and tissue to tissue. Attempts have been made to correlate the concentrations of various elements in teeth with their health

In the article, the grazing incidence technology is first applied to the PIXE (proton induced X-ray emission) analysis. Three pieces of samples were investigated, including the contaminated aluminium substrate, the SIMOX (separated by oxygen implantation) SOI (Silicon on Insulator) sample and the silicon wafer implanted with Fe + . The results reveal that the grazing-incident proton can improve the sensitivity of PIXE in trace analysis, especially for samples contaminated on surface. With the penetration depth of the proton bean decreased, the ratio of the peak area to the detection limit raised observably and the sensitivity near the sample surface increased. (authors)

PIXE analysis method is applied to archaeometry problems. Advantages and disadvantages are emphasized. Some examples are presented which show the difficulties: especially important heterogeneities of ceramics, old coins and metals restrain from the use of this technique. Other analysis systems, less expensive, like electron microbrobe or x-ray fluorescence spectrometry, are compared with conventional PIXE method. The importance of proton microprobe is explained. (author) 40 refs.; 7 figs.; 5 tabs

Micro- or non-destructive analytical approach is an imperative when analysing historical artefacts. Due to its practically non-destructive character, proton induced X-ray spectrometry (PIXE) has become a method of choice for the study of historical documents. In the present paper, use of in-air PIXE method for analysis of iron gall inks applied at handwriting of documents is evaluated. The errors arising from the non-uniform ink deposit, proton penetration depth and size of the proton beam versus width of ink lines, effects of surface roughness, as well as the importance of the PIXE set-up geometry on the accuracy of the results are discussed. It follows that the main problems can be attributed to the fact that PIXE is a surface technique and that the analysis is limited to a small amount of material, while ink deposit on the paper is usually non-uniform in depth as well as on the paper surface. Despite possible systematic uncertainties when applying the PIXE method, good correlation between determinations obtained by PIXE and atomic absorption spectroscopy (AAS) on model samples clearly demonstrate that the errors are well within a reasonable limit of a few percents.

Micro- or non-destructive analytical approach is an imperative when analysing historical artefacts. Due to its practically non-destructive character, proton induced X-ray spectrometry (PIXE) has become a method of choice for the study of historical documents. In the present paper, use of in-air PIXE method for analysis of iron gall inks applied at handwriting of documents is evaluated. The errors arising from the non-uniform ink deposit, proton penetration depth and size of the proton beam versus width of ink lines, effects of surface roughness, as well as the importance of the PIXE set-up geometry on the accuracy of the results are discussed. It follows that the main problems can be attributed to the fact that PIXE is a surface technique and that the analysis is limited to a small amount of material, while ink deposit on the paper is usually non-uniform in depth as well as on the paper surface. Despite possible systematic uncertainties when applying the PIXE method, good correlation between determinations obtained by PIXE and atomic absorption spectroscopy (AAS) on model samples clearly demonstrate that the errors are well within a reasonable limit of a few percents

This paper reports the experimental results of identifying jade by proton induced X-ray emission (PIXE) technique. It is found that the jade can be classified, according to the chemical composition determined by PIXE. The experimental results can differentiate ancient Chinese jade works of art from fakes if the material is the same

Polished copper samples were irradiated with proton beams of 300 and 700 keV at room temperature and at -150 Centigrade. In this work the obtained results are reported when such copper irradiated samples are analysed with Sem, Tem, AFM. The Sem micrographs showed evident changes in surface of these copper samples, therefore an EDAX microanalysis was done for its characterization. additionally, the Tem micrographs showed heaps formation until 200 nm. Its electron diffraction spectra indicated that these heaps consist of a copper compound. Finally with AFM were observed changes in coloration of the irradiated sample surface, as well as changes in texture and rugosity of them. These results show in general that irradiation process with protons which is known as an innocuo process produces changes in the copper properties. (Author)

Proton Induced X-ray Emission, PIXE is a very well established analytical method. This technique of analysis can equally be applied both in vacuum, internal PIXE, and in atmosphere, external PIXE. External PIXE has been applied to material analysis in Van de Graaff laboratory at AEOI using filters and funny filters. Advantages of using these filters have been studied when analysing ancient written documents such as envelopes, inks, and newspapers. This technique clearly demonstrated the differences between new and old inks and papers. More data is needed to show other features of this technique. (author)

PIXE-(Proton Induced X-ray Emission) -an ideal technique for material characterization has been set up at the Folded Tandem Ion Accelerator (FOTIA) at BARC, Trombay. A separate beam line at 45 deg port in which a dedicated PIXE chamber has been installed is being used for PIXE studies. PIXE studies on gold standards were carried out using protons of energy 3.3 MeV. Caritage values of gold standards were obtained which agree well with the certified values. Single element standard solutions (100 μg/ml) for low-Z elements such as Cr, Mn, Fe, Co, Cu and Zn were analyzed by PIXE. Well resolved α and β components of the x-rays were seen with detection limits in the range of 0.8-4 μg/g. (author)

Zinc is a necessary component in the action and structural stability of many enzymes. Some of them are well characterized, but in others, Zn stoichiometry and its association is not known. PIXE has been proven to be a suitable technique for analyzing metallic proteins embedded in electrophoresis gels. In this study, PIXE has been used to investigate the Zn content of enzymes that are known to carry Zn atoms. These include the carbonic anhydrase, an enzyme well characterized by other methods and the cytoplasmic pyrophosphatase of Rhodospirillum rubrum that is known to require Zn to be stable but not how many metal ions are involved or how they are bound to the enzyme. Native proteins have been purified by polyacrylamide gel electrophoresis and direct identification and quantification of Zn in the gel bands was performed with an external proton beam of 3.7 MeV energy

Applicability of EDXRF and PIXE techniques for trace elemental analysis in biology and medicine is demonstrated. Due to increasing importance of the need to determine the role of essential and toxic trace elements in human health and disease, the method of PIXE analysis has assumed great importance in recent years. This method has been found to be particularly useful for biological samples. EDXRF also offers a complimentary method particularly in the range of elements of Z=45 to 60 where the sensitivity of PIXE analysis is not quite adequate. EDXRF can also be usefully employed for other elements of the periodic chart with relatively lesser sensitivity. The work being presented here includes trace element analysis of normal and cancer bearing tissues of Swiss mice, trace element profiles in cancerous human oesophageal tissues, investigations on the effect of toxic metals such as Hg from Ayurvedic drugs on Wister rats, and investigations of blood lead levels of children admitted to Sion Hospital from Dharavi slums of Bombay. The results of these investigations are presented and discussed. (author). 21 refs., 8 figs., 3 tabs

The Bard Hall Ion Beam Facility has developed external proton beams at 1-3 MeV for ion-induced x-ray emission studies of artists' pigments and metallic printers inks. The authors have extended these PIXE measurements to analysis of Athenian Tetradrachms (5th and 6th centuries BC). In both pigment and coin studies they have compared PIXE analyses with those from XRF and electron micro probe for calibration purposes. The Aegean Dendrochronology Project has developed over 5500 years of tree-ring chronologies for the Aegean, Balkans, and Eastern Mediterranean. Included are forest sites adjacent to mining and smelting operations, also sites at the upper timberline where the annual growth-rings might be expected to have picked up fallout from volcanic activity around the world. A preliminary examination of selected rings by PIXE has shown remarkable differences from year to year in the deposition of various elements, notable Zn, Fe, and Cu. The authors propose to look at a number of selected annual ring sequences to see (1) whether one can chart the progress of known metallurgical activity; (2) whether one can find evidence for volcanic effects, both for absolutely-dated volcanoes such as Krakatoa, Tambora, and Sumbawa, and for problematic volcanoes such as Santorini/Thera

Elemental analysis based on the particle induced x-ray emission (PIXE) is a novel technique to analyze trace elements. It is a very simple method, its sensitivity is very high, multiple elements in a sample can be simultaneously analyzed and a few 10 μg of a sample is enough to be analyzed. Owing to these characteristics, the PIXE analysis is now used in many fields (e.g. biology, medicine, dentistry, environmental pollution, archaeology, culture assets etc.). Fundamentals of the PIXE analysis are described here: the production of characteristic x-rays and inner shell ionization by heavy charged particles, the continuous background in PIXE spectrum, quantitative formulae of the PIXE analysis, the detection limit of PIXE analysis, etc. (author)

An accelerator-based study, using proton-induced x-ray emission (PIXE) was performed on four full-cream and four half-cream brands of powdered milk commonly consumed in Jordan. The elements detected in the samples are S, Cl, K, Ca, Fe, Cu, Zn, Br and Rb. The significance of some of these elements is discussed from the viewpoint of nutrition and also their effect on milk processing and dairy technology. The standard reference milk sample, A-11, which is distributed by IAEA was also examined, and the results for trace elements detected are compared with the values certified by IAEA. (author)

A short, comparative evaluation of the methods of neutron activation analysis (NAA), and particle induced X-ray emission (PIXE), is given based on the Proc. of the 2nd international conference on PIXE and its analytical applications. The conference took place June 9-12, 1980, Lund, Sweden. 'The PIXE people have paralleled NAA people - in work, problems and mistakes, summarises the author, but PIXE was proved and established as a standard analytical method.' The method has proved extremely valuable in microprobe applications. (Sz.J.)

In an undergraduate atomic physics experiment, 2.8 MeV protons are used to bombard thick elemental targets. X rays emitted from the targets are detected with a Si(Li) detector, and their energies are measured with a multichannel analyzer. The Kα and Kβ x-ray energies are each plotted as functions of (Z-1) 2 , and the Rydberg energy, Rch, is extracted from the slopes of the resulting lines. The Kα plot gives Rch=14.099±0.025 eV, while the Kβ plot gives 13.557±0.027 eV. The experiment extends the Bohr Theory as discussed in class, serves to introduce PIXE as a quantitative technique for elemental analysis, gives the students experience in using modern instruments which may be used in later experiments, and experience in using uncertainty analysis to decide whether their measurements agree or disagree with other measurements or theoretical calculations. Although the experimental values differ from each other and from the accurately-known value of 13.606 eV by less than 4%, they do not agree to within the experimental uncertainties, forcing students to consider a systematic error arising from their use of the Bohr Theory to derive Moseley's Law

Micro-PIXE (proton-induced X-ray emission) analysis was performed on unfixed and anhydrously prepared sections from developing enamel and dentin from hamsters injected with a single dose of 20 mg NaF/kg body weight. Fluoride, apart from inducing the formation of the characteristic paired response in the enamel (i.e., a hyper- followed by a hypomineralized band in the secretory enamel), also induces the formation of sub-ameloblastic cystic lesions under the transitional and early secretory enamel accompanied by relatively intense hypermineralization of the underlying cystic enamel surface. These cystic lesions, however, were only found to be associated with certain isolated populations of these cells. In addition, these lesions were restricted to the smooth surfaces of the tooth germ only. Cystic lesions such as those seen under the transitional and early secretory ameloblasts were not observed under the fully secretory or maturation stage ameloblasts. Why fluoride induces the formation of cystic lesions in some ameloblast populations while other cells in the same stage of development apparently remain unaffected, is a matter which needs further investigation

The preservation and conservation of mankind cultural heritage has become an important issue worldwide. Non-destructive analytical techniques are suitable, for example, to analyze precious and unique objects of art and archaeology. Among those techniques Particle Induced X-Ray Emission (PIXE) has good advantage to identify elemental composition present in these kinds of objects. The Laboratorio de Analise de Materiais por Feixes Ionicos-LAMFI of the Institute of Physics of the University of Sao Paulo has been installed an external beam facility for PIXE analysis. This new setup is being used for the analysis of archaeological pottery artifacts, paintings and biological tissues (teeth and bones), which are not compatible with the high vacuum of the regular PIXE target chamber. In addition most art and archaeological objects are too large for the evacuated analysis chamber. Applications of this facility will be presented in the analysis of one painting of the beginning of the last century. The chemical elements identified in the painting were Ca, Ti, Cr, Cu, Fe, Zn, Pb and Ba. The PIXE measurements were done non-destructively and no visible damage was observed on the irradiated object. (author)

In the field of cultural heritage 4 He particle beams are often used to perform RBS analysis. In most cases the simultaneously produced X-rays are not considered for PIXE analysis. This paper aims to explore the potentials of 4 He induced X-ray emission (α-PIXE) using 4, 5 and 6 MeV 4 He beams and to compare its performance with that of conventional PIXE with 3 MeV protons. The α-PIXE and α-RBS spectra were collected at the same time in a vacuum chamber. The X-ray yields produced by 6 MeV 4 He beam for K-lines were found to be superior to those of protons for atomic numbers below 25. An additional advantage of α-PIXE is the lower bremsstrahlung background which leads to an improved peak to noise ratio for certain elements

The authors describe the use of proton-induced X-ray emission (PIXE) to analyse the nickel concentrations of the autopsy specimens from victims of Legionnaires' disease. They show that the high nickel concentrations in the lung specimens from the first recognized Legionnaires' cases in Philadelphia in 1976 were due to contamination during the autopsies. Recently the authors have used PIXE to show that the selenium concentrations in the sera of the acutely ill Legionnaires' patients are significantly lower than in their matching convalescent-phase sera. This finding may be related to the patient's response to the disease or to the specific characteristics of the Legionella pneumophila itself. Studies show that the disease is not a rare illness but a worldwide one. General criteria concerning specimen collection are described

A beamline system and experimental setup has been established for elemental analysis using PIXE with an external beam. Experiments for the study of the elemental composition of ancient Chinese potsherds (the Min and Ching ages) were performed. Continuum X-ray spectra from the samples bombarded by 3 MeV protons have been measured with a Si(Li) detector. From the analysis of PIXE data, the concentration of the main elements (Al, Si, K, and Ca) and of more than ten trace elements in the matrices and glazed surfaces were determined. Results for two different potsherds are presented, and those obtained from the glaze colorants are compared with the results of measurements on a Ching blue-and-white porcelain vase.

In recent years, there has been debate regarding the use of the crumb rubber infill in artificial turf on high school and college campuses due to the potential presence of heavy metals and carcinogenic chemicals. We performed Proton-Induced X-Ray Emission (PIXE) analysis of artificial turf infill and blade samples collected from high school and college campuses around the Capital District of NYS to search for potentially toxic substances. Crumb rubber pellets were made by mixing 1g of rubber infill and 1g of epoxy. The pellets and the turf blades were bombarded with 2.2 MeV proton beams from a 1.1-MV tandem Pelletron accelerator in the Union College Ion-Beam Analysis Laboratory and x-ray energy spectra were collected with an Amptek silicon drift detector. We analyzed the spectra using GUPIX software to determine the elemental concentrations of the samples. The turf infill showed significant levels of Ti, Fe, Co, Ni, Cu, Zn, Br, and Pb. The highest concentration of Br in the crumb rubber was 1500 +/-100 ppm while the highest detectable amount of Pb concentration was 110 +/-20 ppm. The artificial turf blades showed significant levels of Ti, Fe, and Zn with only the yellow blade showing concentrations of V and Bi.

Therapeutically important inorganic elements in Agrobacterium rhizogenes-mediated genetically transformed hairy root cultures (HRCs) of a pharmaceutically significant herb Boerhaavia diffusa were quantified using proton induced X-ray emission technique. This was compared with that of roots from the naturally grown donor plant. Two macro-elements (Ca and K) and eight different trace elements namely V, Cr, Mn, Fe, Co, Cu Zn, and Ni were detected and their content was determined. In HRCs of a transformed rhizoclone, calcium and potassium had values which were significantly higher than that of in vivo roots. The concentrations of several trace elements, which are known to have a positive implication in human healthcare, were found to be either comparable (Fe) to that in the natural root samples or higher (Mn, Zn, Cr, Cu, Co) in the transformed rhizoclone. The genetically transformed HRCs can thus serve as a fast-proliferating renewable resource of medicinally useful minerals targeting specific diseases. (author)

Obtaining particulate compositional maps from scanned PIXE (proton-induced X-ray emission) measurements is extremely difficult due to the complexity of analyzing spectroscopic data collected with low signal-to-noise at each scan point (pixel). Multivariate spectral analysis has the potential to analyze such data sets by reducing the PIXE data to a limited number of physically realizable and easily interpretable components (that include both spectral and image information). We have adapted the AXSIA (automated expert spectral image analysis) program, originally developed by Sandia National Laboratories to quantify electron-excited X-ray spectroscopy data, for this purpose. Samples consisting of particulates with known compositions and sizes were loaded onto Mylar and paper filter substrates and analyzed by scanned micro-PIXE. The data sets were processed by AXSIA and the associated principal component spectral data were quantified by converting the weighting images into concentration maps. The results indicate automated, nonbiased, multivariate statistical analysis is useful for converting very large amounts of data into a smaller, more manageable number of compositional components needed for locating individual particles-of-interest on large area collection media

A set of Roman Denarii from the republican to the imperial period (140BC-240AD) has been studied using X-ray fluorescent (XRF) scanning and proton induced x-ray emission (PIXE) techniques. XRF and PIXE are commonly used in the study of cultural heritage objects because they are nondestructive. The combination of these two methods is also unique because of the ability to penetrate the sample with a broader spectrum of depths and energies than either could achieve on its own. The coins are from a large span of Roman history and their analysis serves to follow the economic and political change of the era using the relative silver and copper contents in each sample. In addition to analyzing the samples, the study sought to compare these two common analysis techniques and to explore the use of a standard to examine any shortcomings in either of the methods. Data sets were compared and then adjusted to a calibration curve which was created from the analysis of a number of standard solutions. The concentrations of the standard solutions were confirmed using inductively coupled plasma spectroscopy. Through this we were able to assemble results which will progress the basis of understanding of PIXE and XRF techniques as well as increase the wealth of knowledge of Ancient Roman currency.

Proton-induced X-ray emission (PIXE) has been applied for the determination of 18 elements (Si, K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn, Ga, Rb, Sr, Y, Zr, Nb, Ba and Pb) in two groups of pottery from two different sites in Jordan, Biblical Bozrah (BB) and Amman Citadel (AC). The analysis showed that the elements Zn, Rb, Sr, Zr and Ba were the most useful elements to study to be able to differentiate between the two groups of pottery. (orig.)

In this work, proton induced X-ray emission (PIXE) method was applied for the analysis of ancient Chinese Changsha porcelain produced in the Tang dynasty (AD 618-907). A collection of glazed potsherds was obtained in the complex of the famous kiln site at Tongguan, Changsha city, Hunan province. Studies of elemental composition were carried out on ten selected Changsha potsherds. Minor and trace elements such as Ti, Mn, Fe, Co, Cu, Rb, Sr, and Zr in the material of the porcelain glaze were determined. Variation of these elements from sample to sample was investigated. Details of results are presented and discussed

In this work, proton induced X-ray emission (PIXE) method was applied for the analysis of ancient Chinese Changsha porcelain produced in the Tang dynasty (AD 618-907). A collection of glazed potsherds was obtained in the complex of the famous kiln site at Tongguan, Changsha city, Hunan province. Studies of elemental composition were carried out on ten selected Changsha potsherds. Minor and trace elements such as Ti, Mn, Fe, Co, Cu, Rb, Sr, and Zr in the material of the porcelain glaze were determined. Variation of these elements from sample to sample was investigated. Details of results are presented and discussed.

In this work, proton induced X-ray emission (PIXE) method was applied for the analysis of ancient Chinese Changsha porcelain produced in the Tang dynasty (AD 618-907). A collection of glazed potsherds was obtained in the complex of the famous kiln site at Tongguan, Changsha city, Hunan province. Studies of elemental composition were carried out on ten selected Changsha potsherds. Minor and trace elements such as Ti, Mn, Fe, Co, Cu, Rb, Sr, and Zr in the material of the porcelain glaze were determined. Variation of these elements from sample to sample was investigated. Details of results are presented and discussed.

Particle-induced X-ray emission (PIXE) multielemental analysis of thin film samples are reported. Calibration methods of K and L X-lines are discussed. Application of PIXE analysis to aerosol monitoring, multielement aerosol analysis is described. Results of PIXE analysis of samples from two locations in Hungary are compared with the results of aerosol samples from Scandinavia and the USA. (D.Gy.)

The aim of the work presented in this thesis is to develop a microbeam setup such that small beam spot sizes can be produced routinely, and to investigate the capabilities of the setup for micro-PIXE analysis. The development and performance of the Amsterdam proton microbeam setup are described. The capabilities of the setup for micro-PIXE are shown with an investigation into the presence of trace elements in human hair. (Auth.)

A method for determination of the concentration of mercury in the gaseous phase is described. In the first step of the method a stable sulphur-mercury complex is formed. For this purpose sulphur is deposited on a filter and the investigated gas flows through the filter. Millipore filters and the deposition of sulphur from Na2S2O3 * 5H2O solution were found to be most suitable. The amount of Hg absorbed on the filter was determined by PIXE or by NAA in the second step of the method. An optimization of proton energy was performed in the PIXE analysis to obtain the maximal signal-to-background ratio. The detection limit of the method, expressed as the minimal amount of Hg which has to flow through the filter equals to 30 and 2 ng for PIXE and NAA techniques, respectively. Applications of the method are also described.

In the present work two nuclear micro analysis techniques, synchrotron radiation (SRXRF) and macro proton induced X ray emission (macro PIXE), were used in the homogeneity test of Algae IAEA-413 and Lichen IAEA-338, and the certification of their elemental contents too. Finally, the Ingamell's sampling constant Ks and the relative homogeneity factor HE of some elements in these two RMs were estimated on the base of our macro PIXE results. (author)

Dental composites, made by particles of glass, ceramics and quartz embedded in an organic polymer, develop at a high rate. However, commercial composites are expensive and recently the 'Restacril' biomaterials company became prepared to offer a low-cost alternative. The durability of dental fillings depends not only on biomaterial's gross chemical composition, but also on impurities. These may influence the chemical, mechanical and surface properties of the inorganic particles and modify the composites' clinical behavior. Thus elemental analysis is necessary to improve the biomaterials' quality. Nuclear and atomic methods allow sensitive multielement detection, and we previously analyzed some commercial composites by particle-induced X-ray emission (PIXE). Here we applied PIXE in the qualitative analysis of six new Romanian biomaterials, aiming to compare their nominal and detected composition and paying attention to the impurities. The PIXE measurements were performed with 3 MeV protons at the 8.5 MV NIPNE-HH tandem accelerator, using a hyper pure Ge detector, normal to the beam and connected to a multichannel analyzer and to a computer. Solid samples of composites with a flat surface were fixed at 45 angle, absorber foil of Al 30 mm thick was used, and integration of beam current was done. In all composites PIXE detected mineral elements with Z > 19 down to trace levels. All major nominal elements with Z > 20 - Ca, Sr, Zr, Ba, and Yb - were detected by PIXE. In addition, many minor and trace elements absent from the nominal formulations were seen, including K, Ti, Mn, Fe, Ni, Cu, Zn, Ga, Ag, Cd, Hf, and As/Pb. Such impurities may come from rough materials and preparative technologies. The impurities in Romanian composites are comparable to those in some commercial biomaterials but higher than in other ones. Thus PIXE analysis of mineral elements in Romanian composites, even qualitative, appears useful for quality control and improvement. (authors)

A PIXE system in which large or delicate samples are excited by a low-current external proton beam is described. This system has been used to analyze historical printed books and manuscripts, as well as a large variety of archeological artifacts. The steps used to protect the sample from unnecessary beam current are examined. A recent thorough study of the first volume of the Gutenberg 42-line Bible is described in some detail

There exists a critical need to understand the flow and accumulation of metallic ions, both naturally occurring and those introduced to biological systems. In this paper the results of fabricating thin film elemental biological standards containing nearly any combination of trace elements in a protein matrix are presented. Because it is capable of high elemental sensitivity, particle induced X-ray emission spectrometry (PIXE) is an excellent candidate for in situ analysis of biological tissues. Additionally, the utilization of microbeam PIXE allows the determination of elemental concentrations in and around biological cells. However, obtaining elemental reference standards with the same matrix constituents as brain tissue is difficult. An excellent choice for simulating brain-like tissue is Norland® photoengraving glue which is derived from fish skin. Fish glue is water soluble, liquid at room temperature, and resistant to dilute acid. It can also be formed into a thin membrane which dries into a durable, self-supporting film. Elements of interest are introduced to the fish glue in precise volumetric additions of well quantified atomic absorption standard solutions. In this study GeoPIXE analysis package is used to quantify elements intrinsic to the fish glue as well as trace amounts of manganese added to the sample. Elastic (non-Rutherford) backscattered spectroscopy (EBS) and the 1.734 MeV proton-on-carbon 12C(p,p)12C resonance is used for a normalization scheme of the PIXE spectra to account for any discrepancies in X-ray production arising from thickness variation of the prepared standards. It is demonstrated that greater additions of the atomic absorption standard cause a viscosity reduction of the liquid fish glue resulting in thinner films but the film thickness can be monitored by using simultaneous PIXE and EBS proton data acquisition.

There exists a critical need to understand the flow and accumulation of metallic ions, both naturally occurring and those introduced to biological systems. In this paper the results of fabricating thin film elemental biological standards containing nearly any combination of trace elements in a protein matrix are presented. Because it is capable of high elemental sensitivity, particle induced X-ray emission spectrometry (PIXE) is an excellent candidate for in situ analysis of biological tissues. Additionally, the utilization of microbeam PIXE allows the determination of elemental concentrations in and around biological cells. However, obtaining elemental reference standards with the same matrix constituents as brain tissue is difficult. An excellent choice for simulating brain-like tissue is Norland® photoengraving glue which is derived from fish skin. Fish glue is water soluble, liquid at room temperature, and resistant to dilute acid. It can also be formed into a thin membrane which dries into a durable, self-supporting film. Elements of interest are introduced to the fish glue in precise volumetric additions of well quantified atomic absorption standard solutions. In this study GeoPIXE analysis package is used to quantify elements intrinsic to the fish glue as well as trace amounts of manganese added to the sample. Elastic (non-Rutherford) backscattered spectroscopy (EBS) and the 1.734 MeV proton-on-carbon 12 C(p,p) 12 C resonance is used for a normalization scheme of the PIXE spectra to account for any discrepancies in X-ray production arising from thickness variation of the prepared standards. It is demonstrated that greater additions of the atomic absorption standard cause a viscosity reduction of the liquid fish glue resulting in thinner films but the film thickness can be monitored by using simultaneous PIXE and EBS proton data acquisition

There exists a critical need to understand the flow and accumulation of metallic ions, both naturally occurring and those introduced to biological systems. In this paper the results of fabricating thin film elemental biological standards containing nearly any combination of trace elements in a protein matrix are presented. Because it is capable of high elemental sensitivity, particle induced X-ray emission spectrometry (PIXE) is an excellent candidate for in situ analysis of biological tissues. Additionally, the utilization of microbeam PIXE allows the determination of elemental concentrations in and around biological cells. However, obtaining elemental reference standards with the same matrix constituents as brain tissue is difficult. An excellent choice for simulating brain-like tissue is Norland® photoengraving glue which is derived from fish skin. Fish glue is water soluble, liquid at room temperature, and resistant to dilute acid. It can also be formed into a thin membrane which dries into a durable, self-supporting film. Elements of interest are introduced to the fish glue in precise volumetric additions of well quantified atomic absorption standard solutions. In this study GeoPIXE analysis package is used to quantify elements intrinsic to the fish glue as well as trace amounts of manganese added to the sample. Elastic (non-Rutherford) backscattered spectroscopy (EBS) and the 1.734 MeV proton-on-carbon {sup 12}C(p,p){sup 12}C resonance is used for a normalization scheme of the PIXE spectra to account for any discrepancies in X-ray production arising from thickness variation of the prepared standards. It is demonstrated that greater additions of the atomic absorption standard cause a viscosity reduction of the liquid fish glue resulting in thinner films but the film thickness can be monitored by using simultaneous PIXE and EBS proton data acquisition.

This work presents the characterization of obsydian samples from different mineral sites in Mexico, undertaken by an Ion Beam Analysis: PIXE (Proton Induced X-ray Emission). As part of an intensive investigation of obsidian in Mesoamerica by anthropologists from Mexico National Institute of Anthropology and History, 818 samples were collected from different volcanic sources in central Mexico for the purpose of establishing a data bank of element concentrations of each source. Part of this collection was analyzed by Neutron activation analysis and most of the important elements concentrations reported. In this work, a non-destructive IBA technique (PIXE) are used to analyze obsydian samples. The application of this technique were carried out at laboratories of the ININ Nuclear Center facilities. The samples consisted of of obsydians from ten different volcanic sources. This pieces were mounted on a sample holder designed for the purpose of exposing each sample to the proton beam. This PIXE analysis was carried out with an ET Tandem Accelerator at the ININ. X-ray spectrometry was carried out with an external beam facility employing a Si(Li) detector set at 52.5 degrees in relation to the target normal (parallel to the beam direction) and 4.2 cm away from the target center. A filter was set in front of the detector, to determine the best attenuation conditions to obtain most of the elements, taking into account that X-ray spectra from obsydians are dominated by intense major elements lines. Thus, a 28 μ m- thick aluminium foil absorber was selected and used to reduce the intensity of the major lines as well as pile-up effects. The mean proton energy was 2.62 MeV, and the beam profile was about 4 mm in diameter. As results were founded elemental concentrations of a set of samples from ten different sources: Altotonga (Veracruz), Penjamo (Guanajuato), Otumba (Mexico), Zinapecuaro (Michoacan), Ucareo (Michoacan), Tres Cabezas (Puebla), Sierra Navajas (Hidalgo), Zaragoza

Full text: A Tandem accelerator, NEC Pelletron 5SDH, has been recently installed at Centro Atomico Bariloche, Argentina. This facility provides the local scientific community the opportunity to use nuclear techniques in different fields such as material science, environment (air, soil and food), biology, archaeology, etc.). The ion beam techniques available in our laboratory includes the ones commonly used in material analysis, i. e., PIXE (proton induced X-ray emission), RBS (Rutherford backscattering spectroscopy), PIGE (proton induced gamma ray emission), channeling and ERDA (elastic recall detection analysis). The line used for material analysis consists of a NEC-RC43 Endstation with setups and detectors for all the techniques above mentioned. This communication includes a description of the system facility and the main associated equipment, in particular that for PIXE measurements. In addition, we show some recent applications of PIXE to the study of archaeological ceramics, smokeless gun powders, and the experimental determination of the efficiency or our SDD detector. The detector efficiency was estimated for energies between 0.27 and 25 keV. The method applied is based on the comparison of X-ray characteristic intensities excited by 2-MeV protons in bulk samples with theoretical predictions. The results are compared with efficiency values obtained by the product of the window transmission and the detector quantum efficiency. Element constituents of black, white, brown and ocher pigments from Aguada Culture (600-900 before present) were studied. The results obtained are compared with measurements performed at the Laboratorio de Implantacao Ionica-UFRGS. This study is helpful to interpret the social, political economic and cultural contexts of pre-Inca societies and the interaction among different sites. Traces amounts present in seven smokeless gun powders commonly used in Argentina were determined. The powders were deposited on a carbon tape and the

Full text: A Tandem accelerator, NEC Pelletron 5SDH, has been recently installed at Centro Atomico Bariloche, Argentina. This facility provides the local scientific community the opportunity to use nuclear techniques in different fields such as material science, environment (air, soil and food), biology, archaeology, etc.). The ion beam techniques available in our laboratory includes the ones commonly used in material analysis, i. e., PIXE (proton induced X-ray emission), RBS (Rutherford backscattering spectroscopy), PIGE (proton induced gamma ray emission), channeling and ERDA (elastic recall detection analysis). The line used for material analysis consists of a NEC-RC43 Endstation with setups and detectors for all the techniques above mentioned. This communication includes a description of the system facility and the main associated equipment, in particular that for PIXE measurements. In addition, we show some recent applications of PIXE to the study of archaeological ceramics, smokeless gun powders, and the experimental determination of the efficiency or our SDD detector. The detector efficiency was estimated for energies between 0.27 and 25 keV. The method applied is based on the comparison of X-ray characteristic intensities excited by 2-MeV protons in bulk samples with theoretical predictions. The results are compared with efficiency values obtained by the product of the window transmission and the detector quantum efficiency. Element constituents of black, white, brown and ocher pigments from Aguada Culture (600-900 before present) were studied. The results obtained are compared with measurements performed at the Laboratorio de Implantacao Ionica-UFRGS. This study is helpful to interpret the social, political economic and cultural contexts of pre-Inca societies and the interaction among different sites. Traces amounts present in seven smokeless gun powders commonly used in Argentina were determined. The powders were deposited on a carbon tape and the

Concentrations of thirteen elements in rainwater from the Pittsburgh, Pa., area were analysed by Charged Particle Induced X-ray Emission (PIXE). They were compared to rainwater in a rural area and air particulates in Pittsburgh. Local and non-local contributions are discussed. Washout ratios were calculated and found to be larger for smaller size particles, contrary to general belief. The work demonstrates the convenience of using PIXE.

With elemental analysis we mean the determination of which chemical elements are present in a sample and of their concentration. This is an old and important problem in chemistry. The earliest methods were purely chemical and many such methods are still used. However, various methods based on physical principles have gradually become more and more important. One such method is neutron activation. When the sample is bombarded with neutrons it becomes radioactive and the various radioactive isotopes produced can be identified by the radiation they emit. From the measured intensity of the radiation one can calculate how much of a certain element that is present in the sample. Another possibility is to study the light emitted when the sample is excited in various ways. A spectroscopic investigation of the light can identify the chemical elements and allows also a determination of their concentration in the sample. In the same way, if a sample can be brought to emit X-rays, this radiation is also characteristic for the elements present and can be used to determine the elemental concentration. One such X-ray method which has been developed recently is PIXE. The name is an acronym for Particle Induced X-ray Emission and indicates the principle of the method. Particles in this context means heavy, charged particles such as protons and a-particles of rather high energy. Hence, in PIXE-analysis the sample is irradiated in the beam of an accelerator and the emitted X-rays are studied. (author)

A sample collected from a borehole drilled approximately 10 km ESE of Bragança, Trás-os-Montes, was analysed by standard and high energy PIXE at both CTN (previous ITN) PIXE setups. The sample is a fine-grained metapyroxenite grading to coarse-grained in the base with disseminated sulphides and fine veinlets of pyrrhotite and pyrite. Matrix composition was obtained at the standard PIXE setup using a 1.25 MeV H{sup +} beam at three different spots. Medium and high Z elemental concentrations were then determined using the DT2fit and DT2simul codes (Reis et al., 2008, 2013 [1,2]), on the spectra obtained in the High Resolution and High Energy (HRHE)-PIXE setup (Chaves et al., 2013 [3]) by irradiation of the sample with a 3.8 MeV proton beam provided by the CTN 3 MV Tandetron accelerator. In this paper we present results, discuss detection limits of the method and the added value of the use of the CdTe detector in this context.

A method has been developed and tested for PIXE analysis of soluble and insoluble constituents in a variety of water samples in our surroundings. Insoluble components were filtered on a Nuclepore filter of 0.4-{mu}m pores. For soluble fractions, a target of major components was made from a 0.15-ml filtrate evaporated on a user-made polycarbonate film, and in turn heavy metals in trace amounts were preconcentrated in a PIXE-target through the use of a combination of dibenzyldithiocarbamate-chelation with subsequent condensation into dibenzylidene-D-sorbitol gels. These three kinds of targets were analyzed with a PIXE system of 3-MeV proton beams. The widespread concentrations (several tenths of ppb to a few tens of ppm) of {approx}24 elements from Na to Pb were determined simultaneously in a precision sufficient to reveal the elemental distribution between the soluble and insoluble fractions of various aqueous sample such as river water, rain water and water leaking from disposal sites of industrial wastes. Hence, the methodology for preparing three types of targets promotes the PIXE analysis to a truly effective means for monitoring a water-pollution problem in our surroundings. (author)

A method has been developed and tested for PIXE analysis of soluble and insoluble constituents in a variety of water samples in our surroundings. Insoluble components were filtered on a Nuclepore filter of 0.4-μm pores. For soluble fractions, a target of major components was made from a 0.15-ml filtrate evaporated on a user-made polycarbonate film, and in turn heavy metals in trace amounts were preconcentrated in a PIXE-target through the use of a combination of dibenzyldithiocarbamate-chelation with subsequent condensation into dibenzylidene-D-sorbitol gels. These three kinds of targets were analyzed with a PIXE system of 3-MeV proton beams. The widespread concentrations (several tenths of ppb to a few tens of ppm) of ∼24 elements from Na to Pb were determined simultaneously in a precision sufficient to reveal the elemental distribution between the soluble and insoluble fractions of various aqueous sample such as river water, rain water and water leaking from disposal sites of industrial wastes. Hence, the methodology for preparing three types of targets promotes the PIXE analysis to a truly effective means for monitoring a water-pollution problem in our surroundings. (author)

This work presents a comparative study between the PIXE, proton beams and neutron activation analysis (NAA) techniques, for determination of total zinc concentration. Particularly, soil samples from the Pindorama, Instituto Agronomico de Campinas, Sao Paulo State, Brazil, experimental station have been analysed and measuring the zinc contents in μg/g. The results presented good correlation between the mentioned techniques. The PIXE and NAA analyses have been carried out by using the series S, 2.4 MeV proton beams Pelletron accelerator and the IPEN/CNEN-IEA-R1 reactor, both installed at the Sao Paulo - Brazil university

The external Proton Induced X-Ray Emission (PIXE) facility at Royal Melbourne Institute of Technology has been used to analyse ancient Egyptian glass samples, an Egyptian wall paint fragment and soil pigments. A 0.35 mm diameter beam of 1.6 MeV protons, extracted from the vacuum through an 8 μm gold coated Kapton foil was used. Analysis of the spectra was carried out with the analysis package PIXAN. The analysis of two Egyptian glass samples enabled the partial determination of the colouring transition metals and the manufacturing technique, indicating them to be consistent with 'New Kingdom' glasses

The advantages and disadvantages of PIXE as an analytical method will be summarized. The authors will also discuss the advantages of PIXE as a means of providing interesting and feasible research projects for undergraduate science students

Micro-PIXE is capable of providing spatial distributions of elements in the micro-meter scale and its application to biology is useful to elucidate the cellular metabolism. Since, in this method, a sample target is usually irradiated with proton or α-particle beams in vacuum, beam heating results in evaporation of volatile elements an shrinking of the sample. In order to avoid these side effects, we previously developed a technique of in-air micro-PIXE analysis for samples of cultured cells. In addition to these, analysis of exposed tissue samples from living subjects is highly desirable in biological and medical research. Here, we describe a technique of in-air micro-PIXE analysis of such tissue samples. The target samples of exposed tissue slices from a Donryu rat, in which a tumor had been transplanted, were analyzed with proton micro-beams of 2.6 MeV. We report that the shape of cells and the distribution of volatile elements in the tissue sample remain uncharged when using a target preparation based on a freeze-drying method. (author)

The particle induced X-ray emission technique (PIXE), developed by Johansson and colleagues in Lund, Sweden, in the 70's has been used since then in a high number of studies requiring detection and quantification of trace elements at high sensitivity (better than I mg/kg). PIXE is grouped among the nuclear analytical techniques because the samples are bombarded with particles (protons generally) accelerated in an accelerator. When protons interact with matter an X-Ray spectrum is produced by the deexcitation of atoms in the sample. From this spectrum the elements contained in the sample as well as their concentrations can be determined. In this work we describe the PIXE technique and several applications in the environmental field developed at the Institute of Physics of the National Autonomous University of Mexico (IFUNAM). These practical applications include field studies for analyses of suspended particles in air using tree leaves, irrigation water quality based on heavy metal analyses, and analyses of trace elements in plants cultivated in waste water irrigated soil. (Author)

Particle Induced X-ray Emission (PIXE) has been used as a fast and non-destructive technique for sensitive characterization of ultra thin Al films deposited by evaporation onto Si substrate. In this work the PIXE technique was optimized, using proton beam at different energies and different angles of incidence, for the characterization of ultra thin Al films (few nanometers) deposited onto Si substrate. The PIXE results showed that a proton beam of 300 keV under tilting angle of 80 degree permits an accurate determination of Al with high sensitivity within few minutes of acquisition time and a LOD of less than 0.2 nm. The LOD versus energy and tilting angle will be presented and discussed. (author)

This paper reports the chemical compositions of chicken-blood stone Ji Xue Shi measured by Proton Induced X-ray Emission (PIXE). The experimental result show that for the red portion of chicken-blood stone, the concentration of Hg is as high as 20 wt%, and the concentration of S can be above 10 wt%. For the non-red portion the main chemical compositions are Al 2 O 3 and SiO 2 . The obtained chemical compositions are close to those of kaolinite for Balin chicken-blood stone, and of pyrophyllite for Changhua chicken-blood stone, respectively. So far many Changhua chicken-blood stones and Balin chicken-blood stones were found in China, the PIXE method can be used to explore the provenance of available chicken-blood stones. (author)

The results of the calibration of the PIXE system for analysis of environmental aerosols in the CNM is presented. The system was calibrated in order to lead to the project study of environmental aerosols using PIXE from the qualitative dimension to the quantitative one. Part of this work it was carried out in collaboration with the expert of the IAEA Dr. D. Crumpton. The calibration of the system it was achieved bombarding thin targets of well-known composition with protons of 2.5 MeV. Using this technique it was determined the absolute elementary concentration in samples of atmospheric aerosols. As an example the calculation of the lead concentration in one of them whose result was of 662 ± 49 ng m -3 is presented. This value agrees with the measurements made in the Crocker Nuclear Lab of the UCD. Its are also discussed the reproducibility and precision of the used technique. (Author)

Particle induced X-ray emission (PIXE) analysis is particularly important for the analysis of trace elements of precious samples, being one of the few methods to determine elements with ppm concentration that does not affect sample integrity. A PIXE methodology for trace element analysis in opal was developed. To avoid detector count saturation due to the high number of Si-Kα X-rays generated in the sample, several filters were employed to optimize the reduction of the Si-Kα signal, while maintaining acceptable intensities of the other relevant X-ray lines. Two proton beam energies were tested, to establish the signal to noise ratio in different X-ray energies. Spectra were fitted with the software GUPIX, using a matrix composition determined with electron beam excited energy dispersive X-ray spectrometry. Above the energy of the silicon X-ray, several trace elements were quantified.

PIXE technique was employed in the determination of the major, minor and trace elemental concentrations in finger-nails of 62 healthy young adults (30 females and 32 males), aged between 20 and 37 years. The elemental concentrations in the nails of the analyzed population provide good reference data set for further health studies. The PIXE measurements were carried out using 1.8 MeV collimated proton beam from the 2.5 MV AN-2000 Van de Graaff accelerator at INFN, LNL, Legnaro (Padova), Italy. The results show the presence of twenty elements. Their metabolic roles in humans are presented and discussed. The comparison of our results with those of other authors are also presented

The quantitative estimation of various trace element concentrations in medicinal plants is necessary for determining their effectiveness in treating various diseases and for understanding their pharmacological action. Elemental concentrations of some selected medicinal plants of north east India was measured by proton induced X-ray emission (PIXE) and proton induced γ-ray emission (PIGE) techniques. PIXE measurements were carried out using 2.4 MeV collimated protons from the 3 MV tandetron accelerator of NCCCM, Hyderabad (India) while the PIGE measurements were carried out using 3 MeV protons from the same accelerator in the same laboratory. Accuracy and precision of the techniques were assured by analyzing certified reference materials in the same experimental conditions. Various elements of biological importance in man's metabolism were found to be present in varying concentrations in the studied medicinal plants and no toxic heavy metals were detected. The concentration of the various elements in the medicinal plants and their role in treating various diseases are discussed.

The quantitative estimation of various trace element concentrations in medicinal plants is necessary for determining their effectiveness in treating various diseases and for understanding their pharmacological action. Elemental concentrations of some selected medicinal plants of north east India was measured by proton induced X-ray emission (PIXE) and proton induced {gamma}-ray emission (PIGE) techniques. PIXE measurements were carried out using 2.4 MeV collimated protons from the 3 MV tandetron accelerator of NCCCM, Hyderabad (India) while the PIGE measurements were carried out using 3 MeV protons from the same accelerator in the same laboratory. Accuracy and precision of the techniques were assured by analyzing certified reference materials in the same experimental conditions. Various elements of biological importance in man's metabolism were found to be present in varying concentrations in the studied medicinal plants and no toxic heavy metals were detected. The concentration of the various elements in the medicinal plants and their role in treating various diseases are discussed.

The results of the calibration of the PIXE system for analysis of environmental aerosols in the CNM is presented. The system was calibrated in order to lead to the project study of environmental aerosols using PIXE from the qualitative dimension to the quantitative one. Part of this work it was carried out in collaboration with the expert of the IAEA Dr. D. Crumpton. The calibration of the system it was achieved bombarding thin targets of well-known composition with protons of 2.5 MeV. Using this technique it was determined the absolute elementary concentration in samples of atmospheric aerosols. As an example the calculation of the lead concentration in one of them whose result was of 662 {+-} 49 ng m{sup -3} is presented. This value agrees with the measurements made in the Crocker Nuclear Lab of the UCD. Its are also discussed the reproducibility and precision of the used technique. (Author)

Total charge deposited by a proton beam in an insulator during PIXE analysis has been indirectly determined using a Mylar film coated with cobalt. Elemental concentrations in the samples, pieces of volcanic glass, were obtained and compared to concentrations determined by ICP OES on the same samples. The strong agreement between these results shows the accuracy of the charge determined by this method.

The PIXE method (Particle Induced X-Ray Emission) as analytical method presenting the evolution, the theoretical fundaments, the detection limit, the optimization for operational conditions is evaluated. The applications of the method to air pollution control and aerosol studies in regions such as Antartic, Amazon and other regions are analysed. (M.C.K.) [pt

The purpose of this document is to give an overview of instrumentation for PIXE and Rutherford backscattering analysis, including hardware and software needed to perform the analysis, including detectors, analyzers, data acquisition systems and data analysis software. It also provides some information on accelerators needed for these applications

The PIXE analysis of easel paintings constitutes a challenging task. Despite recognized merits and a few emblematic applications, PIXE has never been routinely applied to these fragile, complex and precious targets. The present work discusses the place of PIXE in the study of easel paintings and opens up perspectives for a more systematic usage of this analytical technique. Progress achieved since decades in the implementation of PIXE to study such fragile cultural heritage artefacts is reviewed, notably at the LABEC laboratory in Italy and at the AGLAE facility of the C2RMF in France. Two specific techniques developed for paintings are detailed and exemplified on Renaissance painting masterpieces: differential PIXE for paint layers depth profiling and multi-scale elemental mapping for the imaging of pigment distribution. Beam-induced damage, a major concern, notably depends on the employed beam fluence in particle/cm"2 or μC/cm"2. After recalling previous works on damage induced in chemical products comparable to pigments, we present the behaviour under different fluences of protons of a few MeV (1–300 μC/cm"2) of targets having high resemblance to historical easel paintings: pellets of specially synthesized lead white pigments, layers of lead white mixed with linseed oil and areas containing lead white of two 19th century paintworks. The results shed new lights on the behaviour of paintworks under the beam and pave the way to strategies for damage mitigation. In particular, the lowering of PIXE performance induced by the decrease of the beam fluence sets a trade-off between risk of damage and gained information which also impacts the PIXE scanning protocol for paintings. As an illustration of an adequate adjustment of this balance, we report the exploratory application of PIXE mapping to a large area of a 19th century easel painting without damage. The recorded elemental maps are compared to elemental maps collected on the same area using laboratory

The PIXE analysis of easel paintings constitutes a challenging task. Despite recognized merits and a few emblematic applications, PIXE has never been routinely applied to these fragile, complex and precious targets. The present work discusses the place of PIXE in the study of easel paintings and opens up perspectives for a more systematic usage of this analytical technique. Progress achieved since decades in the implementation of PIXE to study such fragile cultural heritage artefacts is reviewed, notably at the LABEC laboratory in Italy and at the AGLAE facility of the C2RMF in France. Two specific techniques developed for paintings are detailed and exemplified on Renaissance painting masterpieces: differential PIXE for paint layers depth profiling and multi-scale elemental mapping for the imaging of pigment distribution. Beam-induced damage, a major concern, notably depends on the employed beam fluence in particle/cm2 or μC/cm2. After recalling previous works on damage induced in chemical products comparable to pigments, we present the behaviour under different fluences of protons of a few MeV (1-300 μC/cm2) of targets having high resemblance to historical easel paintings: pellets of specially synthesized lead white pigments, layers of lead white mixed with linseed oil and areas containing lead white of two 19th century paintworks. The results shed new lights on the behaviour of paintworks under the beam and pave the way to strategies for damage mitigation. In particular, the lowering of PIXE performance induced by the decrease of the beam fluence sets a trade-off between risk of damage and gained information which also impacts the PIXE scanning protocol for paintings. As an illustration of an adequate adjustment of this balance, we report the exploratory application of PIXE mapping to a large area of a 19th century easel painting without damage. The recorded elemental maps are compared to elemental maps collected on the same area using laboratory-based scanning

PIXE analysis has been applied to a set of twenty human teeth to determine trace element concentration in enamel from areas suceptible to dental caries (mesial and distal contact points) and in areas less susceptible to the disease (buccal surface), with the aim of determining the possible roles of trace elements in the carious process. The samples were caries-free anterior incisors extracted for periodontal reasons from subjects 10-30 years of age. Prior to extraction of the sample teeth, a detailed dental history and examination was carried out in each individual. PIXE analysis, using a 3 MeV proton beam of 1 mm diameter, allowed the determination of Ca, Mn, Fe, Cu, Zn, Sr and Pb above detection limits. As demonstrated in this work, the enhanced sensitivity of PIXE analysis over electron microprobe analysis, and capability of localised surface analysis compared with the pooled samples require for neutron activation analysis, makes it a powerful and useful technique in dental analysis. (orig.)

Highlights: • The PIXE technique has been used to determine K and Br in a major Nigerian food item. • Samples were analysed using two proton beam energies, namely 1.25 MeV and 2.15 MeV. • Mismatched Ca results reflect its nature and accuracy/precision of the procedure. • Explanations for the presence of the contaminant in the samples are presented. • Other sources originating from erroneous burning of dangerous products suspected. -- Abstract: The alleged use of potassium bromate (KBrO{sub 3}) in bread baking led a few authors to report on the chemical methods for the determination of KBrO{sub 3} levels in bread. In order to examine the potentials of a non chemical particle induced X-ray emission (PIXE) method for this purpose, six sets of samples, each composed of flour, dough and bread from a production batch were analysed. The samples were obtained from six different bakers of bread at Ile-Ife, Nigeria. The flour samples were air-dried while others were freeze dried at about −16 °C. The samples were homogenised in an agate mortar and then pelletised. Samples were analysed at the CTN standard PIXE setup and standard procedures for thick target samples analysis were followed. In some samples significant concentrations of bromine were found. In the present work we present possible explanations for the presence of this potentially dangerous contaminant in the samples.

Highlights: • The PIXE technique has been used to determine K and Br in a major Nigerian food item. • Samples were analysed using two proton beam energies, namely 1.25 MeV and 2.15 MeV. • Mismatched Ca results reflect its nature and accuracy/precision of the procedure. • Explanations for the presence of the contaminant in the samples are presented. • Other sources originating from erroneous burning of dangerous products suspected. -- Abstract: The alleged use of potassium bromate (KBrO 3 ) in bread baking led a few authors to report on the chemical methods for the determination of KBrO 3 levels in bread. In order to examine the potentials of a non chemical particle induced X-ray emission (PIXE) method for this purpose, six sets of samples, each composed of flour, dough and bread from a production batch were analysed. The samples were obtained from six different bakers of bread at Ile-Ife, Nigeria. The flour samples were air-dried while others were freeze dried at about −16 °C. The samples were homogenised in an agate mortar and then pelletised. Samples were analysed at the CTN standard PIXE setup and standard procedures for thick target samples analysis were followed. In some samples significant concentrations of bromine were found. In the present work we present possible explanations for the presence of this potentially dangerous contaminant in the samples

PIXE analysis has been applied to a set of twenty human teeth to determine trace element concentration in enamel from areas suceptible to dental caries (mesial and distal contact points) and in areas less susceptible to the disease (buccal surface), with the aim of determining the possible roles of trace elements in the carious process. The samples were caries-free anterior incisors extracted for periodontal reasons from subjects 10-30 years of age. Prior to extraction of the sample teeth, a detailed dental history and examination was carried out in each individual. PIXE analysis, using a 3 MeV proton beam of 1 mm diameter, allowed the determination of Ca, Mn, Fe, Cu, Zn, Sr and Pb above detection limits. As demonstrated in this work, the enhanced sensitivity of PIXE analysis over electron microprobe analysis, and capability of localised surface analysis compared with the pooled samples require for neutron activation analysis, makes it a powerful and useful technique in dental analysis.

Two nuclear analytical techniques, neutron activation analysis (NAA) and proton induced X-ray emission (PIXE), were used to determine major and trace elements in airborne particulate matter collected during the first fortnight of June 1991 at the La Reina Nuclear Center. NAA detected the presence of 15 elements in the samples. PIXE, for the same samples, allowed the detection of 12 elements. The elements determined by both techniques were Al, Ca, Mn, Fe, Cu, and Zn. A good correlation between results for these elements for each of the two techniques was demonstrated. (author)

The paper concerns the simultaneous PIXE (Particle Induced X-ray Emission) and PIGE (Proton Induced Gamma-ray Emission) analyses of aerosol samples collected in urban areas. The results show that PIGE can detect Li, F, Na, Al, and Si in fly ashes and F, Na, Al and Si in atmospheric aerosol. The PIXE-PIGE technique has also been applied to 80 samples of atmospheric particular matter collected above Milan during the winter and summer months of 1986/7, and the average values of concentrations and enrichment factors are given for the detected elements. (U.K.)

We have been studying the electron-capture in 163 Ho as a method for determining the mass of electron neutrino. The 163 Ho sources were produced with the 164 Dy(p,2n) reaction by means of a method of internal irradiation 2 ). We applied the PIXE method to determine the total number of 163 Ho atoms in the source. Proton beams of 3 MeV and a method of ''external standard'' were employed for nondestructive analysis of the 163 Ho source as well as an additional method of ''internal standard''. (author)

A set of Roman glass fragments, excavated at Sevilla and dated in the 5th century A.D., has been analysed by PIXE and PIGE techniques using the external beam set-up of the 3 MV tandem Pelletron accelerator of the CNA at the University of Sevilla. Using a simple quantification method, based on the indirect charge calculation on the sample by monitoring the X-ray induced by the proton beam on the exit window, the composition of the glasses has been determined. From the obtained results, the use of soda as flux has been inferred and colouring manufacture procedures have been identified.

This study is an attempt to demonstrate how the nuclear micro-PIXE technique can be utilized to investigate ore genesis of geological deposits. Elemental concentrations and distribution profiles in single mineral grains and matrices in a present-day ore deposit on land were measured using the scanning proton microprobe on the 3 MV Tandetron accelerator at King Fahd University of Petroleum and Minerals. Comparing the distribution profiles of some of the trace elements detected it was possible to suggest an organic, sea origin of these deposits. (Author)

A study of the trace elemental concentration in drinking water from Salt Lake City, a residential locality in Calcutta, India, was carried out using the proton induced X-ray emission (PIXE) technique. Samples were collected from overhead tanks, where drinking water is stored for supply to all parts of this residential area. A chelating agent (NaDDTC) was used for the pre-concentration of the trace elements. A large number of elements, namely Ca, Ti, Mn, Fe, Co, Ni, Cu, Zn, As, Sr, Ba, Tl and Pb were detected and the results are discussed

A study of the trace elemental concentration in drinking water from Salt Lake City, a residential locality in Calcutta, India, was carried out using the proton induced X-ray emission (PIXE) technique. Samples were collected from overhead tanks, where drinking water is stored for supply to all parts of this residential area. A chelating agent (NaDDTC) was used for the pre-concentration of the trace elements. A large number of elements, namely Ca, Ti, Mn, Fe, Co, Ni, Cu, Zn, As, Sr, Ba, Tl and Pb were detected and the results are discussed.

The concentrations of 18 major- and minor-elements in 12 Emeralds from different mines and two synthetic ones are measured with proton induced X-ray emission (PIXE) and γ-ray emission (PIGE). The concentration and distribution of 18 elements are used to establish the characteristic finger print pattern of each Emerald. With the help of cluster analysis of SYSTAT statistical package for IBMPC, these finger prints are analysed, from which a quantitative description of the dissimilarities between Emeralds can be given

A large number of phytopharmaceutic drugs are being developed, due to positive effects in various diseases and to high tolerance by the organism. While their medicinally active compounds have been identified, little attention has been paid to their mineral micro- and trace elements. The mineral elements in the drug may have therapeutic or toxic effects which should be properly assessed. Nuclear and atomic methods allow sensitive multielement detection and we previously performed nuclear activation analysis of some Romanian drugs made by plants. Despite this method's high sensitivity, its use is limited by the availability of a nuclear reactor. Particle-induced X-ray emission (PIXE) provides an alternative, and here we examined its potential for the analysis of mineral elements in three commercial phytopharmaceutical preparations, namely, Liv52, Mentat, and Geriforte. The PIXE measurements were performed with 3 MeV protons at the 8.5 MV NIPNE-HH tandem accelerator, using a hyper pure Ge detector, normally oriented and connected to a multichannel analyzer and to a computer; the drug pills were fixed at 45 angle with respect to the beam. In all drugs PIXE detected mineral elements with Z > 16 down to trace levels. Major elements included K, Ca, Fe, Cu, and Zn, and minor/trace amounts of S, Cl, Ti, Cr, Mn, Ni, Ga, Br, Rb, Sr, Hg, and As/Pb were detected. Some differences were seen between the three drugs. Although at trace levels Ga, As, Hg and Pb are not toxic, one should consider that their accumulation might be harmful and caution seems recommendable on long-term cure. Most of the other elements are known to exert a positive biological role, and both in major and trace levels they may contribute to the therapeutic action. Thus PIXE analysis of mineral elements in phytopharmaceutic drugs, even qualitative, is useful for evaluating the benefits and risks in the therapy. (authors)

Particle Induced X-ray Emission (PIXE) is a very sensitive analytical technique for determinations of trace elements. But the number of users is limited because there are not so much accelerators which can be used easily. On the other hand, PIXE is a typical machine analysis which can easily analyze automatically and make online data acquisition system. If there is useful online data handling system then PIXE analysis should be more useful for many persons. Therefore we develop to online PIXE facility at Tokyo Institute of Technology VdG laboratory and use it for environmental educations. (author)

The paper describes a novel experiment characterized by the development of a confocal geometry in an external Micro-PIXE set-up. The position of X-ray optics in front of the X-ray detector and its proper alignment with respect to the proton micro-beam focus provided the possibility of carrying out 3D Micro-PIXE analysis. As a first application, depth intensity profiles of the major elements that compose the patina layer of a quaternary bronze alloy were measured. A simulation approach of the 3D Micro-PIXE data deduced elemental concentration profiles in rather good agreement with corresponding results obtained by electron probe micro-analysis from a cross-sectioned patina sample. With its non-destructive and depth-resolving properties, as well as its feasibility in atmospheric pressure, 3D Micro-PIXE seems especially suited for investigations in the field of cultural heritage

The Japan Steel Works, Ltd. has been supplying a very small sized cyclotron (Baby Cyclotron) to hospitals and research facilities. The cyclotron is designed to produce short-lived radioisotopes for medical use. In the present study, this cyclotron is modified so that it can serve for PIXE analysis. The PIXE (particle induced X-ray emission) technique has the following features: (1) Down to 1 ng of trace material in a sample (mg - μg) can be detected, (2) An analysis run is completed in one to ten minutes, permitting economical analysis for a large number of samples, (3) Several elements can be analyzed simultaneously, with an almost constant sensitivity for a variety of elements ranging from aluminum to heavy metals, (4) Analysis can be performed nondestructively without a chemical process, and (5) The use of microbeam can provide data on the distribution of elements with a resolution of several μm. Software for analysis is developed to allow the modified equipment to perform peak search, background fitting, and identification and determination of peaks. A study is now being conducted to examine the performance of the equipment for PIXE analysis of thin samples. Satisfactory results have been obtained. The analysis time, excluding the background correction, is 5-10 min. (Nogami, K.)

The main goal of this work was to determine the concentration of Sn 2+ ions in cells of the yeast Saccharomyces cerevisiae and to correlate their quantity with the genotoxicity of intracellularly accumulated metal ions. The intracellular metal content of yeast cells was determined by PIXE (particle-induced X-ray emission) after cell exposure to SnCl 2 . To that end, a thick target protocol was developed for PIXE analysis. The samples were irradiated with a 2 MeV proton beam, while the induced X-rays were detected with a high-purity germanium detector. The results of the toxicity of SnCl 2 and the PIXE analysis performed with two different yeast strains (haploid and diploid) suggest that the exposure of haploid and diploid yeast to Sn 2+ induces DNA lesions and that the absorption depends on the genetic background of each strain

Particle induced x-ray emission (PIXE) measurements were performed on thin samples prepared from different rabbit tissues, using 3 MeV proton beam for inducing x-rays from the animal tissues. This method is very sensitive and very small amounts of trace elements can be detected. Cadmium, one of the most toxic elements which can be concentrated in animal and human tissues due to environmental pollution, was detected with a limit of 0.7 ppm. The trace element concentrations obtained by PIXE were compared to those measured by atomic absorption spectrometry. PIXE method is proposed for routine analysis at the Veterinary and Food Investigating Service, Budapest, Hungary. (D.Gy.) 6 refs.; 3 figs

Degradation of paper caused by beam irradiation was investigated from a viewpoint of discoloration in PIXE analysis and its application to the paper samples of archaeology. Two types of paper (Japanese paper and fine quality paper) were tested in in-air PIXE analysis with 3 MeV protons. The degree of discoloration was quantitatively measured by the use of a colorimeter. The degree of discoloration was different for each tested paper and corresponded to the radiation dose of ions. It is resulted that even the in-air PIXE analysis should be carefully applied to archaeological treasures. Because discoloration of all tested paper decreased gradually at first but then increased after a few weeks. However, this phenomenon can be used to develop a technique of funny coloration. (author)

Degradation of paper caused by beam irradiation was investigated from a viewpoint of discoloration in PIXE analysis and its application to the paper samples of archaeology. Two types of paper (Japanese paper and fine quality paper) were tested in in-air PIXE analysis with 3 MeV protons. The degree of discoloration was quantitatively measured by the use of a colorimeter. The degree of discoloration was different for each tested paper and corresponded to the radiation dose of ions. It is resulted that even the in-air PIXE analysis should be carefully applied to archaeological treasures. Because discoloration of all tested paper decreased gradually at first but then increased after a few weeks. However, this phenomenon can be used to develop a technique of funny coloration. (author)

This paper reports on the use of PIXE and RBS (resonant and non-resonant RBS) implemented with proton beams to simultaneously analyse light and heavy elements in materials of cultural heritage significance, as exemplified by Russian icons or in lead seals. It is shown that in spite of its poor mass resolution RBS with protons can provide useful information when combined with PIXE. In the case of Russian icons, it is possible to discriminate between an Au-Ag bilayer and an alloy of these metals in the gilds. However, when applied to lead seals RBS with protons encounters a significant limitation due to some deficiency in the available computer programs used for spectrum processing

An optimized readout configuration based on a charge preamplifier with pulsed-reset has been designed for Silicon Drift Detectors (SDDs) to be used in Particle Induced X-ray Emission (PIXE) measurements. The customized readout electronics is able to manage the large pulses originated by the protons backscattered from the target material that would otherwise cause significant degradation of X-ray spectra and marked increase in dead time. In this way, the excellent performance of SDDs can be exploited in high-quality proton-induced spectroscopy of low- and medium-energy X-rays. This paper describes the designed readout architecture and the performance characterization carried out in a PIXE setup with MeV proton beams.

The PIXE(Proton Induced X-ray Emission) method is used in various fields owing to its high sensitivity. This method can be used to analyze multiple elements in a short time and therefore is suitable for the analysis of large quantities of environmental samples. We researched the effect of removing footwear in a room on indoor aerosol pollution. The concentration of aerosol particles in the case that footwear was not removed was 5 times larger than in the case when footwear was removed. We were able to identify a source of air pollution using both the results of PIXE analysis and information on wind direction. We applied PIXE analysis to investigate airborne yellow sand, which originals from the Gobi desert. By analyzing each yellow sand particle, hazardous yellow sand could be detected. We also applied PIXE analysis to river water pollution. River water samples were collected at a number of points along a river. The dilution of metallic elements by the river water was observed. Thus, it was shown that monitoring systems using the PIXE method are very useful for monitoring environmental pollution. (author)

The Gossip detector, being a GridPix TPC equipped with a thin layer of gas, is a promising alternative for Si tracking detectors. In addition, GridPix would be an interesting way to read out the gaseous phase volume of bi-phase Liquid Xe cryostats of v-less double beta decay and rare event (i.e. WIMP) search experiments.

The Gossip detector, being a GridPix TPC equipped with a thin layer of gas, is a promising alternative for Si tracking detectors. In addition, GridPix would be an interesting way to read out the gaseous phase volume of bi-phase Liquid Xe cryostats of v-less double beta decay and rare event (i.e. WIMP) search experiments.

Both industrial and road traffic pollutions were studied by PIXE by means of determination of trace elements accumulated in different plant tissues from affected areas. The method was improved by the application of an intermediate atmosphere in the target chamber. The PIXE method was proved to be adequate and convenient for monitoring many of the pollutants. (author)

Silverpoint drawings from the Renaissance are among the most precious and rarest treasures of graphical art. Our research group is particularly interested in the analysis of silverpoint drawings by Albrecht Duerer (1471-1528). A very sensitive and non-destructive analytical method, either spatially resolved synchrotron-radiation induced X-ray fluorescence (SY-XRF) or proton-induced X-ray emission (PIXE), is needed to determine the chemical composition of the very faint silver marks on such drawings. Duerer drawings from the collection of the Albertina, Vienna, were analyzed to amend existing data on Duerer drawings. For this purpose an external-beam PIXE setup was installed at the Vienna Environmental Research Accelerator (VERA). It allows to analyze a spot of {approx}0.15 mm on the object in air with 3 MeV protons, and to detect the emitted X-rays that are characteristic for the chemical composition with very good sensitivity and without harming the precious objects. After successful measurements on artificial test samples, four original silverpoint drawings were investigated: two portraits from Albrecht Duerer's very early period (self-portrait and portrait of his father) and two drawings from Duerer's sketch book of his travel to the Netherlands 1520/21.

The University of Montreal EN Tandem accelerator and a Si (Li) X-ray detector were used for a PIXE (Proton Induced X-ray emission) trace element analysis of a selection of wines. Quantitative measurements of the concentrations of the sixteen trace elements Na, Mg, Al, Si, P, S, Cl, K, Ca, Cr, Mn, Fe, Co, Cu, Zn, and Br were made. To optimize the sensitivity, spectra were recorded at 1.0 MeV proton energy for elements with Z 19. The absolute concentrations of the trace elements were determined by doping the samples of wine with 1000 ppm of vanadium for the 1.0 MeV bombardments, and 1000 ppm of yttrium for the 3.0 MeV irradiations. The targets were prepared by depositing a few microliters of the wine onto a Nuclepore filter

The development of an external PIXE facility on the 1 MV Tandetron accelerator at RMIT has led to a wide range of research possibilities. A proton beam, generated inside a vacuum is brought into air via an Au coated Kapton foil exit window (thickness 8μm, diameter 0.35mm). Monitoring of the beam intensity is achieved by detecting backscattered protons from the inside Au coating on the window. Artefacts, which may be too large to be placed inside the vacuum, are positioned in the beamline opposite the exit window. An optical system consisting of a CCD camera, alignment laser and two mirrors allows viewing of a region of the target 10mm x 10mm. This technique provides quantitative analysis of elements in the pigments used in paintings and on ceramics, which is a valuable tool in art conservation and authentication. Application of the technique to a ceramic sample from the historic house 'Viewbank' is described

Five widely used anti-asthmatic medicinal plants of north-eastern region of India have been investigated by using Proton Induced X-ray Emission (PIXE) and Proton Induced Gamma ray Emission (PIGE) techniques. The elements namely K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se and Br were detected with different concentrations (in ppm level) by PIXE technique whereas light elements namely F, Na, Mg, Al, P and Cl by PIGE technique in the studied plants. No toxic heavy metals such as Hg, Pb, Cd were detected. Analysis was performed on thick targets (pellets) prepared using the powders of specimens through a series of processing steps. Thick targets of plant based Certified Reference Materials (CRMs) were served as standardization of PIXE and PIGE set up. The trace elements present in the studied plants have been correlated with their medicinal properties.

Five widely used anti-asthmatic medicinal plants of north-eastern region of India have been investigated by using Proton Induced X-ray Emission (PIXE) and Proton Induced Gamma ray Emission (PIGE) techniques. The elements namely K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se and Br were detected with different concentrations (in ppm level) by PIXE technique whereas light elements namely F, Na, Mg, Al, P and Cl by PIGE technique in the studied plants. No toxic heavy metals such as Hg, Pb, Cd were detected. Analysis was performed on thick targets (pellets) prepared using the powders of specimens through a series of processing steps. Thick targets of plant based Certified Reference Materials (CRMs) were served as standardization of PIXE and PIGE set up. The trace elements present in the studied plants have been correlated with their medicinal properties.

An Artificial Neural System, ANS, has been designed to operate in the analysis of spectra obtained from a PIXE (Proton Induced X-ray Emissions) application. The special designed ANS was used in the calculation of the concentrations of the major elements in the samples. Neural systems using several feed-forward ANN of similar topology working in parallel were trained with error back propagation algorithm using sets of spectra of known elemental concentrations. Following the training phase of the neural networks, other PIXE spectra were analyzed with this methodology providing unknown elemental concentrations. ANS results were compared with results obtained by traditional computer codes like AXIL and GUPIX, obtaining correlations factors close to one. The rather short time required to process each spectrum, of the order of microseconds, allows fast analysis of a large number of samples. Here we present applications of ANS in the PIXE analyses of samples of organic nature like liver, gills and muscle from fishes. ANS results were compared with elemental concentrations obtained in a previous application where a single ANN was used for each analyzed element. PIXE analyses were performed at the Nuclear Physics Laboratory of the University of Chile, using 2.2 MeV proton beams provided by a Van de Graaff accelerator. (author)

Full Text Available We have made a wide phylogenetic survey of Pix proteins, which are constituents of vertebrate centrioles in most eukaryotes. We have also surveyed the presence and structure of flagella or cilia and centrioles in these organisms, as far as is possible from published information. We find that Pix proteins are present in a vast range of eukaryotes, but not all. Where centrioles are absent so are Pix proteins. If one considers the maintenance of Pix proteins over evolutionary time scales, our analysis would suggest that their key function is to make cilia and flagella, and the same is true of centrioles. Moreover, this survey raises the possibility that Pix proteins are only maintained to make cilia and flagella that undulate, and even then only when they are constructed by transporting ciliary constituents up the cilium using the intraflagellar transport (IFT system. We also find that Pix proteins have become generally divergent within Ecdysozoa and between this group and other taxa. This correlates with a simplification of centrioles within Ecdysozoa and a loss or divergence of cilia/flagella. Thus Pix proteins act as a weathervane to indicate changes in centriole function, whose core activity is to make cilia and flagella.

We have made a wide phylogenetic survey of Pix proteins, which are constituents of vertebrate centrioles in most eukaryotes. We have also surveyed the presence and structure of flagella or cilia and centrioles in these organisms, as far as is possible from published information. We find that Pix proteins are present in a vast range of eukaryotes, but not all. Where centrioles are absent so are Pix proteins. If one considers the maintenance of Pix proteins over evolutionary time scales, our analysis would suggest that their key function is to make cilia and flagella, and the same is true of centrioles. Moreover, this survey raises the possibility that Pix proteins are only maintained to make cilia and flagella that undulate, and even then only when they are constructed by transporting ciliary constituents up the cilium using the intraflagellar transport (IFT) system. We also find that Pix proteins have become generally divergent within Ecdysozoa and between this group and other taxa. This correlates with a simplification of centrioles within Ecdysozoa and a loss or divergence of cilia/flagella. Thus Pix proteins act as a weathervane to indicate changes in centriole function, whose core activity is to make cilia and flagella.

To optimal utilization of the 150 kV ion accelerator facilities and to govern the analysis technique using ion accelerator, the research and development of low energy PIXE technology has been done. The R and D for hardware of the low energy PIXE installation in P3TM have been carried on since year 2000. To support the R and D of PIXE accelerator facilities in harmonize with the R and D of the PIXE hardware, the development of PIXE software for analysis is also needed. The development of database of PIXE software for analysis using turbo Pascal computer code is reported in this paper. This computer code computes the ionization cross-section, the fluorescence yield, and the stopping power of elements also it computes the coefficient attenuation of X- rays energy. The computer code is named PIXEDASIS and it is part of big computer code planed for PIXE analysis that will be constructed in the near future. PIXEDASIS is designed to be communicative with the user. It has the input from the keyboard. The output shows in the PC monitor, which also can be printed. The performance test of the PIXEDASIS shows that it can be operated well and it can provide data agreement with data form other literatures. (author)

In this work we describe an application of particle-induced X-ray emission (PIXE) to the elemental analysis of polished otoliths of whitefish. Two spots on polished otoliths were irradiated; one spot in the core region of the otolith and another one close to the edge. The irradiations were performed in air with a collimated 0.5 mm proton beam. The ratio of the strontium concentrations in the two spots was used to distinguish between different ecotypes (river, sea, lake) of whitefish. Criteria on the ratios were suggested for identification of the whitefish forms. The results were compared to results of μ-beam PIXE scans as well as multi-point scans with the 0.5 mm proton beam. The measuring set-up and the results are discussed.

The three-stage BCR sequential step reference extraction procedure was applied to the reference material BCR CRM 601, especially developed for fractionation studies. Extracted fractions were analyzed for Cr, Ni, Zn, Cd, and Pb, by k 0 -standardized instrumental neutron activation (k 0 INAA) and proton induced X-ray emission (PIXE), and flame atomic absorption spectrometry (FAAS). Sample preparation procedures were developed for both k 0 INAA and PIXE techniques, related to the evaporation of the solutions in order to get solid samples for neutron and proton irradiation. Quality control was assessed by intercomparison of the analytical results obtained by the applied techniques, which included results for a few certified reference materials. In the extracted fractions, chromium concentration was not determined accurately by both nuclear techniques. Concerning Cd, Ni, Pb, and Zn, the results were in general in good agreement with the certified values and FAAS. Some incomplete separation of the residue might have occurred. (author)

In this work we describe an application of particle-induced X-ray emission (PIXE) to the elemental analysis of polished otoliths of whitefish. Two spots on polished otoliths were irradiated; one spot in the core region of the otolith and another one close to the edge. The irradiations were performed in air with a collimated 0.5 mm proton beam. The ratio of the strontium concentrations in the two spots was used to distinguish between different ecotypes (river, sea, lake) of whitefish. Criteria on the ratios were suggested for identification of the whitefish forms. The results were compared to results of μ-beam PIXE scans as well as multi-point scans with the 0.5 mm proton beam. The measuring set-up and the results are discussed.

A statistical evaluation of the association between different elements contained in atmospheric aerosol particles has been made using the microPIXE technique. We derived elemental maps of Al, Si, S, Ca, Cl, K, Fe, Mg spatial distribution on the surface of a Nuclepore filter sample. The microPIXE measurements are validated by comparison to conventional PIXE and SEM-EDAX. Then, the spatial coherence of the different elements is analysed using statistical methods. The elements are not homogeneously distributed and the association among specific elements can be identified. MicroPIXE and factorial analysis can be coupled to understand the state of mixing of the different elements on the filter surface

Elemental PIXE analysis of cave sediments, minerals, pigments of the prehispanic paintings and obsidian cutting tools from caves in Baja California Sur has been carried out with a 0.7 MeV proton beam. The elements analysed in this sample set (Al to Co) provide an idea of the environment of the caves. The obsidian data analysis suggests that the human communities who made these painting used more than one obsidian source to manufacture cutting tools. (orig.)

Plantago ovata Forsk - an economically important medicinal plant - was analyzed for trace elements and chlorophyll in a study of the effects of gamma radiation on physiological responses of the seedlings. Proton-induced X-ray emission (PIXE) technique was used to quantify trace elements in unirradiated and gamma-irradiated plants at the seedling stage. The experiments revealed radiation-induced changes in the trace element and chlorophyll concentrations.

A large collection of emeralds of various occurrences has been analysed by PIXE/PIGE in view to establish a compositional database. Major elements (Be, Si, Al) and trace elements (Li, F, Na, Mg, Ca, Rb, Cs and transition metals) are determined using an external 3 MeV proton micro-beam. Elemental micro-mapping permits to select the useful provenance tracers. This database was applied to infer the origin of several ancient emeralds set on historical jewels

Bioaccumulation by micro-alga in the ocean was simulated in nutritive seawater containing known amounts of trace metals, and the concentration factors for Fe, Zn and Cd were measured by PIXE. Trace transition metals in nearshore seawater were removed by Chelex-100. Then a culture solution was prepared by adding known amounts of trace metals and nutritive salts to the purified seawater. Marine micro-algae (Nannochloropsis sp., and Phaeodactylum sp.,) were purely cultured in the culture solution. An interested metal ion was added to the culture solution (0.01-5.0 mg/l). Alga in 10 ml of the culture solution was collected on a polycarbonate filter (pore size: 1.0 ) by suction filtration and subjected to 2.9 MeV proton bombardment. Na, Mg, Al, Si, P, S, Cl, K, Ca, Cr, Mn, Fe, Zn and Cd were simultaneously determined. PIXE multi-element analysis was possible using less than 1 mg of analytical sample. The quantity of the metal in the alga was increased in proportion to the concentration in the culture solution. The concentration factors for Zn, Fe and Cd were measured, e.g., 10200 ± 300 ml/g to Zn for Phaeodactylum. The trend of the affinity for the trace metals in the case of Nannochloropsis was Fe 3+ > Zn 2+ > Pb 2+ > Cd 2+ . (author)

PIGE and PIXE techniques were employed for the determination of the major, minor and trace elemental concentrations in chewing sticks of pharmacological importance namely: Butyrospermum paradoxum, Garcinia kola, Distemonanthus benthamianus, Bridelia ferruginea, Anogeissus leiocarpus, Terminalia glaucescens and Fagara rubescens, respectively. The concentration of fluorine which is very important for human dental enamel was specially determined using the {sup 19}F(p,p`{gamma}){sup 19}F reaction. For decades these chewing sticks when used alone without toothpastes have proven to be very efficient, effective and reliable in cleaning the teeth of many people particularly in Nigeria and some other countries in Africa. The teeth of users are usually very strong, clean, fresh and devoid of germs and caries. Even with the advent of modern toothpastes with special additions of fluorine, the use of these popular and efficient chewing sticks is still unabated. Many people including the elite use them solely, a few others combine their use with modern toothpastes and brush. Proton beams produced by the 7 MV CN and 2.5 MV AN 2000 Van de Graaff accelerators at INFN, Laboratori Nazionali di Legnaro (LNL), Padova, Italy were used for the PIGE and PIXE analysis, respectively. Results of this novel study are presented and discussed. (orig.).

PIGE and PIXE techniques were employed for the determination of the major, minor and trace elemental concentrations in chewing sticks of pharmacological importance namely: Butyrospermum paradoxum, Garcinia kola, Distemonanthus benthamianus, Bridelia ferruginea, Anogeissus leiocarpus, Terminalia glaucescens and Fagara rubescens, respectively. The concentration of fluorine which is very important for human dental enamel was specially determined using the 19 F(p,p'γ) 19 F reaction. For decades these chewing sticks when used alone without toothpastes have proven to be very efficient, effective and reliable in cleaning the teeth of many people particularly in Nigeria and some other countries in Africa. The teeth of users are usually very strong, clean, fresh and devoid of germs and caries. Even with the advent of modern toothpastes with special additions of fluorine, the use of these popular and efficient chewing sticks is still unabated. Many people including the elite use them solely, a few others combine their use with modern toothpastes and brush. Proton beams produced by the 7 MV CN and 2.5 MV AN 2000 Van de Graaff accelerators at INFN, Laboratori Nazionali di Legnaro (LNL), Padova, Italy were used for the PIGE and PIXE analysis, respectively. Results of this novel study are presented and discussed. (orig.)

In this work the results of the analysis are presented, using the PIXE technique (Proton Induced X-ray Emission), in soil samples of the El Bordo, Vetagrande, Zacatecas, before and after subjecting them to a lixiviation process for the recovering of gold, silver and mercury. This community is part of the mining region nearer to the Zacatecas city municipality, region in which the mining exploitation dates from the colonial time. During almost 350 years the 'yard benefit' method was used or amalgamation with mercury, process that besides having used big quantities of mercury, generated a great quantity of mineral waste calls 'mine wetlands', those that were accumulating, crawled by the rains, toward the streams that end in the prey 'The Pedernalillo'. The dispersion of wetlands them it has extended from the prey until the communities of Tacoaleche, Zoquite, Lampotal and El Bordo, embracing an approximate area of 16 x 2 Km 2 and forming with the course of the time an accumulated of several millions of tons. In order to determining if the process of recovery of gold, silver and mercury make soluble to other contained metals in these wastes, samples were gathered in an area of 600 m 2 in the community of The Border, Vetagrande, Zacatecas. Half of the samples were subjected to the lixiviation process in a local metal recovery plant and the other part was analyzed without processing. The analysis of both types of samples by means of the PIXE was carried out in the University of Arizona in Tucson. (Author)

PIXE and HEBS techniques were employed for the measurement of the concentrations of the major, minor and trace elements in Nigerian coal samples from a major deposit. The samples were irradiated with 2.55 MeV protons from the 3 MeV tandem accelerator (NEC 3 UDH) in Lund. The PIXE results are reported and compared with an earlier work on Nigerian coal using FNAA and INAA analytical techniques while the HEBS results are compared with ASTM previous results. The results corroborate the assertion that Nigerian coals are of weak and noncoking grades with low sulphur (0.82-0.99%) and relatively high hydrogen (4.49-5.16%) contents. The motivation for this work is partly due to the projected usage of coal as metallurgical feedstocks and as fuel, and partly because of the genuine concern about the concomitant environmental effects of the increased burning of coal. The knowledge of the concentration of all elements is important for the characterization of coal and the determination and control of its products. Economic parameters such as the ash contents and calorific values are associated with the concentrations of coal's constituents. (author). 11 refs, 1 fig., 4 tabs

Hypertrophic scars are a particular type of scar that can form after any type of dermal injury. They are unsightly, red, elevated above normal skin level, itchy and painful. At present no-one knows why these scars form. Due to the differences between scar tissue and normal skin it was decided to analyse skin tissue which at a later date would be compared to scar tissue. Spit skin graft (epidermis) samples as well as full thickness skin (epidermis to dermis) tissue were analysed using PIXE and RBS with a 2 MeV proton beam. The epidermis was compared to the dermis to see if there were any variations between the two. In all the samples P, S, Cl, K, Ca, Fe, and Cd were detected and in a majority of the samples Zn and Ba were found, using PIXE. It was found that, between the epidermis and dermis, there was an significant increase in P in the epidermis in both full thickness and split skin graft samples. Complementary elemental analysis was also performed using neutron activation, and Br, Na and Zn were detected. (author)

PIGE and PIXE techniques were employed for the determination of the major, minor and trace elemental concentrations in chewing sticks of pharmacological importance namely: Butyrospermum paradoxum, Garcinia kola, Distemonanthus benthamianus, Bridelia ferruginea, Anogeissus leiocarpus, Terminalia glaucescens and Fagara rubescens, respectively. The concentration of fluorine which is very important for human dental enamel was specially determined using the 19F(p, p'γ) 19F reaction. For decades these chewing sticks when used alone without toothpastes have proven to be very efficient, effective and reliable in cleaning the teeth of many people particularly in Nigeria and some other countries in Africa. The teeth of users are usually very strong, clean, fresh and devoid of germs and caries. Even with the advent of modern toothpastes with special additions of fluorine, the use of these popular and efficient chewing sticks is still unabated. Many people including the elite use them solely, a few others combine their use with modern toothpastes and brush. Proton beams produced by the 7 MV CN and 2.5 MV AN 2000 Van de Graaff accelerators at INFN, Laboratori Nazionali di Legnaro (LNL), Padova, Italy were used for the PIGE and PIXE analysis, respectively. Results of this novel study are presented and discussed.

The knowledge of the intracellular distribution of biological relevant metals is important to understand their mechanisms of action in cells, either for physiological, toxicological or pathological processes. However, the direct detection of trace metals in single cells is a challenging task that requires sophisticated analytical developments. The combination of micro-PIXE with RBS and STIM (Scanning Transmission Ion Microscopy) allows the quantitative determination of trace metal content within sub-cellular compartments. The application of STIM analysis provides high spatial resolution imaging (< 200 nm) and excellent mass sensitivity (< 0.1 ng). Application of the STIM-PIXE-RBS methodology is absolutely needed when organic mass loss appears during PIXE-RBS irradiation. This combination of STIM-PIXE-RBS provides fully quantitative determination of trace element content, expressed in μg/g, which is a quite unique capability for micro-PIXE compared to other micro-analytical methods such as the electron and synchrotron x-ray fluorescence. Examples of micro-PIXE studies for sub-cellular imaging of trace elements in various fields of interest will be presented: in patho-physiology of trace elements involved in neurodegenerative diseases such as Parkinson's disease, and in toxicology of metals such as cobalt. (author)

The PIXE analysis of easel paintings constitutes a challenging task. Despite recognized merits and a few emblematic applications, PIXE has never been routinely applied to these fragile, complex and precious targets. The present work discusses the place of PIXE in the study of easel paintings and opens up perspectives for a more systematic usage of this analytical technique. Progress achieved since decades in the implementation of PIXE to study such fragile cultural heritage artefacts is reviewed, notably at the LABEC laboratory in Italy and at the AGLAE facility of the C2RMF in France. Two specific techniques developed for paintings are detailed and exemplified on Renaissance painting masterpieces: differential PIXE for paint layers depth profiling and multi-scale elemental mapping for the imaging of pigment distribution. Beam-induced damage, a major concern, notably depends on the employed beam fluence in particle/cm{sup 2} or μC/cm{sup 2}. After recalling previous works on damage induced in chemical products comparable to pigments, we present the behaviour under different fluences of protons of a few MeV (1–300 μC/cm{sup 2}) of targets having high resemblance to historical easel paintings: pellets of specially synthesized lead white pigments, layers of lead white mixed with linseed oil and areas containing lead white of two 19th century paintworks. The results shed new lights on the behaviour of paintworks under the beam and pave the way to strategies for damage mitigation. In particular, the lowering of PIXE performance induced by the decrease of the beam fluence sets a trade-off between risk of damage and gained information which also impacts the PIXE scanning protocol for paintings. As an illustration of an adequate adjustment of this balance, we report the exploratory application of PIXE mapping to a large area of a 19th century easel painting without damage. The recorded elemental maps are compared to elemental maps collected on the same area using

A set of samples containing airborne particulate matter (in two particle size fraction PM10 and PM2,5) collected during five months from November 2006 to April 2007 in a urban area of Havana City were analyzed by Particle-Induced X-ray Emission (PIXE) technique and the concentrations of 14 elements (S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Br and Pb) were determined consistently in both particle size fractions with minimum detection limits in the range of ng/m3. A Gent air sampler was used for the aerosol collection in PM10 and PM2,5 particles simultaneously and the PIXE elemental analysis were performed using a proton beam of 2.5 MeV from the 2 MV Van de Graff Tandetron Accelerator at the ININ PIXE Laboratory in Mexico. The analytical database provided by PIXE was statistically analyzed in order to determine the promising local pollution sources. The statistical techniques of Multivariate Factor Analysis in combination with the Principal Component Analysis methods were applied to this data and allowed identifying five main pollution sources of airborne particulate matter (PM10 and PM2,5) collected in this area. The main (local) identified sources were: soil dust, sea spray, industry, fossil fuel combustion from motor vehicles and burnings or incinerations of diverse materials. A general discussion about these results is presented in this work. (Author)

The tomographic reconstruction of biological specimens requires robust algorithms, able to deal with low density contrast and low element concentrations. At the IST/ITN microprobe facility new GPU-accelerated reconstruction software, JPIXET, has been developed, which can significantly increase the speed of quantitative reconstruction of Proton Induced X-ray Emission Tomography (PIXE-T) data. It has a user-friendly graphical user interface for pre-processing, data analysis and reconstruction of PIXE-T and Scanning Transmission Ion Microscopy Tomography (STIM-T). The reconstruction of PIXE-T data is performed using either an algorithm based on a GPU-accelerated version of the Maximum Likelihood Expectation Maximisation (MLEM) method or a GPU-accelerated version of the Discrete Image Space Reconstruction Algorithm (DISRA) (Sakellariou (2001) [2]). The original DISRA, its accelerated version, and the MLEM algorithm, were compared for the reconstruction of a biological sample of Caenorhabditis elegans – a small worm. This sample was analysed at the microbeam line of the AIFIRA facility of CENBG, Bordeaux. A qualitative PIXE-T reconstruction was obtained using the CENBG software package TomoRebuild (Habchi et al. (2013) [6]). The effects of pre-processing and experimental conditions on the elemental concentrations are discussed.

The Chaliyar river, located in Kerala, India has shown preoccupying pollution levels, that constitute a threat to public health and the ecological system. PIXE and PIGE techniques have been employed to measure the elemental concentrations in the river sediment samples. Thick targets were prepared out of the sediment samples collected from various sites along the course of the river. The measurements were carried out using 3 MeV proton beam obtained from 3 MV Tandem pelletron accelerator at Institute of Physics, Bhubaneswar. The elemental concentrations, especially that of heavy metals, at different sites are discussed in detail. Our results show that sediments from a site where the industrial activities are high are significantly high in concentrations of heavy metals (Cr, Ni, Cu, Zn, Hg and Pb) than those collected from non-industrial sites. The measured values are compared with the average composition of unpolluted river sediments and other national and international river sediments. (author)

In this paper the environmental impact of several phosphogypsum piles sited in the southwest of Spain is studied using multielemental analysis by PIXE of 12 salt marsh and soil samples collected in their surroundings. The piles are used to store the main by-product formed in the production of phosphoric acid and phosphate fertilizers. The samples collected were bombarded with 2.5 MeV protons from the 3 MV Van de Graaff accelerator in the ITN at Sacavèm (Portugal), and 20 elements from Al to Pb were detected. The results obtained reinforce previous radioanalytical determinations concerning the significant radioactive contamination pathways (leaching or/and dissolution of elements by water from the piles) and the negligible pathways (atmospheric and direct aquatic transport).

Trace element analysis is one of the most important field in analytical chemistry. There are several instrumental techniques which are applied for determinations of microscopic elemental content. The PIXE (Proton Induced X-ray Emission) technique is one of the nuclear techniques that is commonly applied for such purpose due to its multielemental analysis possibilities. The aim of this study was to establish the optimal conditions for target preparation procedure. In this paper two different approaches to the topic are presented and widely discussed. The first approach was the traditional pellet technique and the second one was mineralization procedure. For the analysis soft tissue such as liver was used. Some results are also presented on water samples. (author)

The technique of Proton Induced X-ray Emission is a suitable method for the elemental analysis of obsidian samples and artefacts. By comparing the elemental composition of obsidian artefacts with those of known sources of obsidian and identifying similarities, the likely origin of the sample can be discovered and information about resource procurement gained. A PIXE facility has now been established at the Auckland University Research Accelerator Laboratory, AURA2. It offers a rapid, multi-element, non-destructive method of characterisation of obsidian samples ranging from small chips to large pieces. In an extensive survey of Mayor Island obsidian, a discrimination has been made between the different locations of obsidian deposits on the island. In addition, using the database developed at AURA2, artefacts from the site of Opita, Hauraki Plains, have been sourced. (Author). 18 refs., 8 figs., 7 tabs., 1 appendix

Ancient Iranian silver coins minted in various parts of the ancient Iran from Transoxiana to Mesopotamia over a time span of 460 years (247BC-208AD) during Parthians dynasty were analysed by PIXE with a 2.2 MeV proton beam. Forty seven silver coins owned by Tamashagah-e-Pool (museum of money) in Tehran were examined in this study. The possible correlation between the composition of coins and the minting time or the minting location of coins has been the prime objective of the present study. Elemental analysis of ancient coins could also reveal the direct relation with the political and economical situation and also with the metallurgy of the minting time. Results on the contents of principal component elements (Fe, Ni, Cu, As, Br, Ag, Sn, Sb, Ba, Au and Pb) are presented and discussed. (author)

We present results of the determination of Cd- and Zn-dopants in InP single crystals using the PIXE and RBS spectrometry at our 2 MeV Van de Graaff accelerator. The (100) oriented crystals were doped by thermodiffusion of Cd and Zn atoms. For concentration and localization measurements we used the ion-channeling technique and energy dispersive spectrometry of proton induced X-ray emission (PIXE). Angular scans of the K-lines of In, Cd and Zn were obtained. The strong In X-rays were attenuated by a rhodium foil in front of the low energy Ge detector. The PIXE-channeling results were compared with SIMS and Hall-effect measurements. (orig.)

Ceramics objects are the most common artifacts found during excavation of archaeological sites and often depicts cultural habits and manufacturing technologies of the culture. The determination of macroscopic and microscopic characteristics of the ceramic objects such as the ceramic porosity, addition of tempers in the clay, main chemical components and the trace elements present in the ceramic can reveal many aspects about the manufacturing processes used by the culture, its degree of development, the provenance of the raw materials and the exchange networks. Also the radiography can help to investigate the manufactured processes, the size of the tempers used and the conservation status of the artifacts. In this present work two non-destructive techniques, radiography and PIXE (Particle Induced X-ray Emission) were used to characterize one set of thirty-six pre-Hispanic ceramic pieces from the Chimu Culture conserved in the Museu de Arqueologia e Etnologia (MAE/USP). The PIXE analyses performed in the external beam setup at LAMFI (Laboratório de Análise de Materiais por Feixes Iônicos) allowed measure the principal chemical elements such as Al, Si, K, Ti, Fe and Ca, present in this group of pieces. X-ray imagings allowed identify the manufacture processes, the granularity of the tempers used, as well as the similarity and the differences between the pieces studied.

We have performed an elemental analysis of atmospheric aerosol samples collected at Piseco Lake in Upstate New York using proton induced x-ray emission spectroscopy (PIXE). This work is part of a systematic study of airborne pollution in the Adirondack Mountains. Of particular interest is the sulfur content that can contribute to acid rain, a well-documented problem in the Adirondacks. We used a nine-stage cascade impactor to collect the samples and distribute the particulate matter onto Kapton foils by particle size. The PIXE experiments were performed with 2.2-MeV proton beams from the 1.1-MV pelletron accelerator in the Union College Ion-Beam Analysis Laboratory. X-Ray energy spectra were measured with a silicon drift detector and analyzed with GUPIX software to determine the elemental concentrations of the aerosols. A broad range of elements from silicon to zinc were detected with significant sulfur concentrations measured for particulate matter between 0.25 and 0.5 μm in size. The PIXE analysis will be described and preliminary results will be presented.

We have performed an elemental analysis of aerosol and soil samples collected at Piseco Lake in Upstate New York using proton induced X-ray emission spectroscopy (PIXE). This work is part of a systematic study of airborne pollution in the Adirondack Mountains. Of particular interest is the sulfur content that can contribute to acid rain, a well-documented problem in the Adirondacks. We used a nine-stage cascade impactor to collect the aerosol samples near Piseco Lake and distribute the particulate matter onto Kapton foils by particle size. The soil samples were also collected at Piseco Lake and pressed into cylindrical pellets for experimentation. PIXE analysis of the aerosol and soil samples were performed with 2.2-MeV proton beams from the 1.1-MV Pelletron accelerator in the Union College Ion-Beam Analysis Laboratory. There are higher concentrations of sulfur at smaller particle sizes (0.25-1 μm), suggesting that it could be suspended in the air for days and originate from sources very far away. Other elements with significant concentrations peak at larger particle sizes (1-4 μm) and are found in the soil samples, suggesting that these elements could originate in the soil. The PIXE analysis will be described and the resulting data will be presented.

Pytoremediation using an arsenic hyperaccumulator, Petris vittata L., has generated an increasing interest worldwide due to both environmentally sound and cost effectiveness. However the mechanism of arsenic accumulation by this fern is not clear at this time. This study examined the uptake of arsenate (As(V)) and arsenite (As(III)) by a hydroponic culture of Pteris vittata using both in-air submilli-PIXE for different parts of the fern and in-air micro-PIXE for the tissue cells. These PIXE analysis systems used 3 MeV proton beams from a 4.5-MV single-ended Dynamitron accelerator at Tohoku University, Japan. The fern took up both arsenate and arsenite from hydroponic solutions which were spiked with 50 mg of arsenic per litter. Final amount of arsenic accumulation in the fern is 1,500 mg per kg (wet weight) of the plant biomass in arsenite treatment and 1,100 mg per kg in arsenate treatment. Arsenic accumulation was not observed at the root parts of the ferns. The in-vivo mapping of elements by submilli-PIXE analyses on the fern laminas showed the arsenic accumulation in the edges of a pinna. The micro-PIXE analyses revealed arsenic maps homogeneously distributed in cells of the lamina, stem and rhizome of the fern. These results indicate that arsenic, both arsenate and arsenite in a contaminated medium are translocated quickly from roots to fronds of Pteris vittata, and distributes homogeneously into tissue cells of the fern laminas. (author)

In order to test whether some candidate reference materials show homogeneity that can satisfy quality control of the PIXE technique, six bottles of each of the two Candidate RM's - Lichen (IAEA 338) and Algae (IAEA 413) were tested. Four different tests were performed. First, two pellets from each bottle were prepared and analysed using broad beam (φ = 5 mm) PIXE. Second and third was analysis of homogeneity using scanning focussed beam at the nuclear microprobe. Scans of 50x50 μm 2 and 240x260 μm 2 were performed. Finally, individual grains with composition differing from the rest of the sample, were analysed using PIXE and RBS. (author)

The permissible level of the Pb content in wine varies in the range of 200-300 {mu}g/l in different countries. These values are below the detection limit for standard PIXE spectrometry. Initiated by an intercomparison action of The International Measurement Evaluation Programme (IMEP, Geel, Belgium), an attempt was made to lower the detection limit of PIXE without introducing any additional chemical steps. Wine samples of 5 ml were gradually condensed below an infrared lamp and 8 {mu}l aliquots were taken from time to time and pipetted onto filter paper. The samples were analysed by standard PIXE technique, with the analyte addition method used for calibration. A detection limit of about 50 ppb was finally achieved. Comparing this value to the permissible levels, this simple and fast technique can be used for screening purposes. As an application, the lead content of three Hungarian market wines was also measured.

During the year 2000, an exercise was organized to make a intercomparison of widely available software packages for analysis of particle induced X ray emission (PIXE) spectra. This TECDOC describes the method used in this intercomparison exercise and presents the results obtained. It also gives a general overview of the participating software packages. This includes basic information on their user interface, graphical presentation capabilities, physical phenomena taken in account, way of presenting results, etc. No recommendation for a particular software package or method for spectrum analysis is given. It is intended that the readers reach their own conclusions and make their own choices, according to their specific needs. This TECDOC will be useful to anyone involved in PIXE spectrum analysis. This TECDOC includes a companion CD with the complete set of test spectra used for intercomparison. The test spectra on this CD can be used to test any PIXE spectral analysis software package

The permissible level of the Pb content in wine varies in the range of 200-300 μg/l in different countries. These values are below the detection limit for standard PIXE spectrometry. Initiated by an intercomparison action of The International Measurement Evaluation Programme (IMEP, Geel, Belgium), an attempt was made to lower the detection limit of PIXE without introducing any additional chemical steps. Wine samples of 5 ml were gradually condensed below an infrared lamp and 8 μl aliquots were taken from time to time and pipetted onto filter paper. The samples were analysed by standard PIXE technique, with the analyte addition method used for calibration. A detection limit of about 50 ppb was finally achieved. Comparing this value to the permissible levels, this simple and fast technique can be used for screening purposes. As an application, the lead content of three Hungarian market wines was also measured

Proton microbeam is a powerful tool for two-dimensional elemental analysis. The analysis is based on Particle Induced X-ray Emission (PIXE) and Particle Induced Gamma-ray Emission (PIGE) techniques. The paper outlines the principles and instruments, and describes the dental application has been done in JAERI Takasaki. (author)

Araxa, in Brazil, is a naturally high background area located in the State of Minas Gerais with a population of about 93 672 people. Araxa is historical city famous for its mineral water sources and mud from Termas de Araxa spa, which have been used for therapeutic, and recreation purposes. Other important aspect of economy of the city are mining and metallurgic industries. In the Araxa area is located the largest deposit of pyrochlore, a niobium mineral, and also a deposit of apatite, a phosphate mineral both containing Th and U associated to crystal lattice. The minerals are obtained from open pit mines, the minerals are processed in industrial also located in city of Araxa, these plants process the pyrochlore and apatite to obtain the Fe-Nb alloy and the concentrate of phosphate, respectively. Studies were developed in this area to assessment the occupational risk of the workers due to exposure to dust particles during the routine working, however very few studies evaluated the water contamination outside the mines in order to determine the metal (stables elements) concentrations in water and also the concentrations of the radionuclides in water. This paper presents the previous results of a study to identify and determine the concentrations of metals (stables elements) and radionuclides in river around the city. The water from these rivers is used as drinking water and irrigation water. The water samples were collected in different rivers around the Araxa city and the samples were analyzed using PIXE technique. A proton beam of 2 MeV obtained from the van de Graaff electrostatic accelerator was used to induce the characteristic X-rays. S, K, Ca, Cr, Mn, Fe, Ni, Zn, Ba, Pb and U were identified in the mass spectrum of the samples. The elemental mass concentrations were compared using a non-parametric statistical test. The results of the statistical test showed that the elemental mass concentrations did not present the same distribution. These results indicated

Most previous research measures fluorescence properties over the macroscopic regime. Properties of individual microscopic grains could be significantly different than those measured over the macroscopic scale. Until recently, it was difficult to measure properties of individual fluor grains. Existing characterization techniques like scanning electron microscopy are not practical, since the resulting fluorescence masks the electron surface profile. Starting in September 2000, a research program was initiated at the Acadiana Research Laboratory to determine microscopic fluorescence properties for selected inorganic rare earth compounds. The initial phase of this program utilized microscopic proton induced X-ray emission (μPIXE) to characterize the elemental composition of individual fluor grains. Results show that both individual grains and small clusters of grains could be seen using μPIXE. Maps of this type can be used to estimate grain dimensions for the selected rare earth fluor. This technique is a new and innovative method to characterize a fluor material

Atmospheric aerosol samples were collected using an 8-stage cascade impactor or an automatic time sequence step sampler at Jomo Langma, Zhangye at the edge of Gobi Desert and Beijing. Element concentration were analyzed by PIXE (proton induced X-ray emission) technique. The data were analyzed by APCA (absolute principal component analysis) to determine the principal components. The sources and contribution to the aerosol in the above three regions were discussed. The result shows that the PIXE has high sensitivity, multi-element capability, high speed and non-destruction advantages. APCA analytical method can effectively determine the aerosol components in urban area, and it also can distinguish between local components and remote components in the area far from the pollution resources

Chemical composition analysis is one of the most important research aspects to provide scientific proof for the technical origin and development of Chinese ancient glass. Proton induced X-ray emission (PIXE) technique is a kind of multi-element quantitative analysis method with high sensitivity and without destruction of samples. Chemical composition of the Western Han dynasty glass garment flakes, which were excavated from Yangzhou city, was analyzed by PIXE, quantitatively. It was found that these glass flakes were attributed to PbO-BaO-SiO 2 glass originated in China. These flakes all consist of a glass core and a corroded outer layer with different thickness. There are relatively higher PbO, P 2 O 5 and CaO, while much lower BaO and SiO 2 in the corroded layers than in the glass cores. The experimental results were discussed

Full text: A recent rise of social attention towards ethical consumerism, ethical jewellery, blood diamonds and the traceability of gemstones has challenged scientists to construct analytical systems to deliver in line with such expectations by offering traceability solutions. It is important to develop traceability protocols for gemstones and pearls that are ethically traded, as this will further encourage members of the trade to engage in ethical and fair trade practices. Of various kinds of available methods, Proton/particle Induced X-ray Emission (PIXE) seems to be robust and promising in this context because of its trace element analysis capabilities without destruction. The authors conducted both vacuum and in-air experiments to optimize conditions to identify important peaks and to quantify the signals that correspond to gemstone materials from specific geographic origins. PIXE results for cultured pearls from Micronesia and commercial-quality crystals from Pakistan, both sources of fair trade gemstone materials, will be presented. (author)

Milk and milk products constitute an important ingredient of human nutrition all over the world. Macro mineral contents like sodium, potassium, calcium, phosphorus and micro mineral contents like iron, copper, zinc, manganese of some varieties of powder milk available in the local market have been investigated by Proton Induced X-Ray Emission (PIXE). These elements are essential for the optimal functioning of various chemical processes taking place in the human body. Any toxic element present in milk can also be detected simultaneously. PIXE is a powerful and universal elemental analysis technique with high detection sensitivity for elements with Z> 11 in the periodic table. The technique is non-destructive and may be applied to samples as small as a cell to a large painting. (author)

Full text: A recent rise of social attention towards ethical consumerism, ethical jewellery, blood diamonds and the traceability of gemstones has challenged scientists to construct analytical systems to deliver in line with such expectations by offering traceability solutions. It is important to develop traceability protocols for gemstones and pearls that are ethically traded, as this will further encourage members of the trade to engage in ethical and fair trade practices. Of various kinds of available methods, Proton/particle Induced X-ray Emission (PIXE) seems to be robust and promising in this context because of its trace element analysis capabilities without destruction. The authors conducted both vacuum and in-air experiments to optimize conditions to identify important peaks and to quantify the signals that correspond to gemstone materials from specific geographic origins. PIXE results for cultured pearls from Micronesia and commercial-quality crystals from Pakistan, both sources of fair trade gemstone materials, will be presented. (author)

To investigate the cause of Alzheimer's disease (senile dementia of Alzheimer's disease type), we examined aluminium (Al) in the brain (hippocampus) of patients with Alzheimer's disease using heavy ion (5 MeV Si 3+ ) microprobe particle-induced X-ray emission (PIXE) analysis. Heavy ion microprobes (3 MeV Si 2+ ) have several times higher sensitivity for Al detection than 2 MeV proton microprobes. We also examined Al in the brain of these patients by energy dispersive X-ray spectroscopy (EDX). (1) Al was detected in the cell nuclei isolated from the brain of patients with Alzheimer's disease using 5 MeV Si 3+ microprobe PIXE analysis, and EDX analysis. (2) EDX analysis demonstrated high levels of Al in the nucleolus of nerve cells in frozen sections prepared from the brain of these patients. Our results support the theory that Alzheimer's disease is caused by accumulation of Al in the nuclei of brain cells. (author)

High energy PIXE is a useful and non-destructive tool to characterize multi-layer thick samples such as cultural heritage objects. In a previous work, we demonstrated the possibility to perform quantitative analysis of simple multi-layer samples using high energy PIXE, without any assumption on their composition. In this work an in-depth study of the parameters involved in the method previously published is proposed. Its extension to more complex samples with a repeated layer is also presented. Experiments have been performed at the ARRONAX cyclotron using 68 MeV protons. The thicknesses and sequences of a multi-layer sample including two different layers of the same element have been determined. Performances and limits of this method are presented and discussed.

A review of the fundamentals and actual state in Mexico of the pixe (particle induced X- ray emission) technique are done. Elemental identification in samples of Mexico City's atmosphere taken in two sites is performed using this technique. A 3 MeV proton beam is used to irradiate the samples. Factors (Bremsstrahlung and interference) that difficult the use of the technique are discussed. The sensitivity of the method is enhanced as a main characteristic. It is shown that tje pixe technique together with an appropriate sampling system can be used to study environmental aerosols. Identified elements are bromine, lead, copper, iron, zinc, titanium, vanadium, calcium, potassium, chlorine, sulfur and silicon. Temporal variations of these elements are discussed. (Author)

The methodology used to carry out the characterization of the ceramic material is based on the employment of two analytical techniques. The first one, X-ray diffraction (XRD), it is used to determine the composition of the present minerals and the general composition of the pastes. The second, X-ray emission induced by protons (PIXE), it is used to determine the composition of trace elements and bigger elements. The combined use of these techniques even allows to differ among ceramic pastes of very similar compositions. Although these techniques can be used in a non destructive way, in the case of ceramic studies it is required of taking a small quantity of sample of the potsherd, this is pulverized to homogenize the material and to carry out the XRD analysis. The same powder can be used to prepare a pellet and to carry out the PIXE analysis. (Author)

The contamination of heavy metals in food becomes a serious problem. We analyzed oolong tea from different production areas by PIXE using very simple sample preparation and examined trace elements contained in these samples. From the results of this experiment, we could know oolong tea which analyzed in this experiment contains various minerals such as K, Ca, P, S, Cl, Fe, Mn, Cu and Cr but not toxic element of As which detection limit of PIXE was lower than the standard values given by the food hygiene law in Japan. (author)

The trace elements preserved on sharp edges of stone tools may provide some information about the worked material, which in turn may serve for the reconstruction of users way of life. Since the amount of the deposited worked material is minute, it can only be detected by sensitive fluorescence techniques, induced by electrons in the electron microscopes, or by light ions from the particle accelerators (PIXE). The trace element deposition was studied by PIXE for a set of experimental tools used for working bone and wood, and for a set of archaeological artefacts dating from the late paleolithic till neolithic period. (author)

A cascade impactor and PIXE technique were used to estimate the air pollution in a urban area. PIXE is a multielementar method and for all elements the detection limit is about nanograms. The particle size distribution was determined using a cascade impactor with six stage. It collects the particles in the respirable and invaluable of aerosol. The samples were collected close to Planetary in Rio de Janeiro City. The results indicate that particles containing Cu, Zn, Ni, Fe, Mn, Cr, V, Ti, Ca and K. The particle was in the respirable fraction of with MMAD,2 μm. (author)

PIXE technique on the analysis of vehicle exhaust particulate is introduced. The clement composition and concentration of particulate are obtained. Some elements which are related to environmental pollution such as sulfur lead, silicon and manganese, were analyzed and discussed in detail by PIXE technique Nowadays although unleaded gasoline is widely used, the lead concentration is still very high in exhaust particulate. The concentrations of silicon and manganese in exhaust particulate from different model vehicles are also quite high from measurements. It shows that an evidence for exhaust pollution control could be provided from this work

A series of PIXE analyses has been performed on glazes from terracotta sculptures of the Italian Renaissance and on reference standards. The problems related to the investigation of such heterogeneous materials are discussed and the experimental uncertainties are evaluated, for each element, from the PIXE analysis of standard glasses. Some examples from artefacts coming from Italian collections are given. This research has been conducted in the framework of the COST-G1 European action.

A series of PIXE analyses has been performed on glazes from terracotta sculptures of the Italian Renaissance and on reference standards. The problems related to the investigation of such heterogeneous materials are discussed and the experimental uncertainties are evaluated, for each element, from the PIXE analysis of standard glasses. Some examples from artefacts coming from Italian collections are given. This research has been conducted in the framework of the COST-G1 European action

The usefulness and accuracy of PIXE as an analytical tool in the study of trace elements in environmental samples of the Brazilian Cerrado are discussed. The report lists actual and forthcoming publications resulting from the study. The mechanism of exchange of elements in solution in water to aerosols has been investigated. For details of the procedure the reader is referred to an earlier report

PIXE measurements were performed on various calcareous materials including identified bone residues, human cremains, and samples of disputed origin. In a forensic application, the elemental analysis suggests that the origin of a sample suspectly classified as human cremains can tentatively be identified as a mixture of sandy soil and dolomitic limestone

The effects of the degree of non-uniformity of the particle beam, matrix composition and matrix thickness in a quantitative elemental analysis by particle induced X-ray emission (PIXE) are discussed and a criterion to evaluate the resulting degree of uncertainty in the mass determination by this method is established. (Auth.)

Full text: Several studies have been carried out in order to investigate the toxicological properties of some chemical elements in different type of biological samples. lon beam techniques, in particular PIXE, have been successfully used to analyze the elemental composition of food, beverage, plants and animal tissues. In this context, the PIXE line of the lon Implantation Laboratory (Porto Alegre, Brazil) have been used in the last few years to study food and beverage processing and biological specimens exposed to contaminated environment. The aim of this study is to present some of our results using PIXE analysis applied to toxicological research field. For instance, a recent published research [1] investigated the genotoxic and mutagenic effects in tobacco farmers exposed to metal-based formulated pesticides. Levels of Mg, AI, CI, Zn, Cr and Br, elements associated with DNA damage, were higher in the blood samples of tobacco farmers exposed to pesticide than in the non-exposed group. The occupational genotoxicity among copper smelters was also investigated [2]. The elemental content of blood samples were analyzed by PIXE. DNA damage in the peripheral blood Iymphocytes of workers exposed to copper smelter was observed. However, no clear correlation was found between the metal content and DNA damage. [1] F. R. da Silva, J. da Silva, M. C. AlIgayer, C. F. Simon, J. F. Dias, C. E. I. dos Santos, M. Salvador, C. Branco, N. B. Schneider, V. Kahl, P. Rohr, K. Kvitko, J. Hazard. Mat., 225-226 (2012) 81-90. (author)

Full text: Several studies have been carried out in order to investigate the toxicological properties of some chemical elements in different type of biological samples. lon beam techniques, in particular PIXE, have been successfully used to analyze the elemental composition of food, beverage, plants and animal tissues. In this context, the PIXE line of the lon Implantation Laboratory (Porto Alegre, Brazil) have been used in the last few years to study food and beverage processing and biological specimens exposed to contaminated environment. The aim of this study is to present some of our results using PIXE analysis applied to toxicological research field. For instance, a recent published research [1] investigated the genotoxic and mutagenic effects in tobacco farmers exposed to metal-based formulated pesticides. Levels of Mg, AI, CI, Zn, Cr and Br, elements associated with DNA damage, were higher in the blood samples of tobacco farmers exposed to pesticide than in the non-exposed group. The occupational genotoxicity among copper smelters was also investigated [2]. The elemental content of blood samples were analyzed by PIXE. DNA damage in the peripheral blood Iymphocytes of workers exposed to copper smelter was observed. However, no clear correlation was found between the metal content and DNA damage. [1] F. R. da Silva, J. da Silva, M. C. AlIgayer, C. F. Simon, J. F. Dias, C. E. I. dos Santos, M. Salvador, C. Branco, N. B. Schneider, V. Kahl, P. Rohr, K. Kvitko, J. Hazard. Mat., 225-226 (2012) 81-90. (author)

A number of ancient Iranian silver coins belonging to Khosrau II (592-626 A.D.) minted during Sasanians dynasty were analyzed using proton induced X-ray emission (PIXE) technique. The 2 MeV proton beam with a current of 2-3 nA from AEOI, Van de Graaff accelerator was used to bombard the coins. The characteristic X-rays emitted from the samples, were detected by a Si(Li) detector from ORTEC with an energy resolution of 170 eV at 5.9 keV. The detector was placed in the beam direction at 135 deg. The elements Cl, Ca, Ti, Mn, Fe, Cu, Au and Pb were observed in the coins along with the major component silver. The percentage of silver varied between 85.87 and 93.39%. The possible correlation between the composition of coins and the minting time or the minting location of coins was the prime goal. There was a negative correlation between copper and silver. The weight of coins varied between 4.02 and 4.30 g. Going through the results, it seems that the local mines were used to die-strike the coins. The obtained results are in good agreement with archaeological records.

A number of ancient Iranian silver coins belonging to Khosrau II (592-626 A.D.) minted during Sasanians dynasty were analyzed using proton induced X-ray emission (PIXE) technique. The 2 MeV proton beam with a current of 2-3 nA from AEOI, Van de Graaff accelerator was used to bombard the coins. The characteristic X-rays emitted from the samples, were detected by a Si(Li) detector from ORTEC with an energy resolution of 170 eV at 5.9 keV. The detector was placed in the beam direction at 135°. The elements Cl, Ca, Ti, Mn, Fe, Cu, Au and Pb were observed in the coins along with the major component silver. The percentage of silver varied between 85.87 and 93.39%. The possible correlation between the composition of coins and the minting time or the minting location of coins was the prime goal. There was a negative correlation between copper and silver. The weight of coins varied between 4.02 and 4.30 g. Going through the results, it seems that the local mines were used to die-strike the coins. The obtained results are in good agreement with archaeological records.

A number of ancient Iranian silver coins belonging to Khosrau II (592-626 A.D.) minted during Sasanians dynasty were analyzed using proton induced X-ray emission (PIXE) technique. The 2 MeV proton beam with a current of 2-3 nA from AEOI, Van de Graaff accelerator was used to bombard the coins. The characteristic X-rays emitted from the samples, were detected by a Si(Li) detector from ORTEC with an energy resolution of 170 eV at 5.9 keV. The detector was placed in the beam direction at 135 deg. The elements Cl, Ca, Ti, Mn, Fe, Cu, Au and Pb were observed in the coins along with the major component silver. The percentage of silver varied between 85.87 and 93.39%. The possible correlation between the composition of coins and the minting time or the minting location of coins was the prime goal. There was a negative correlation between copper and silver. The weight of coins varied between 4.02 and 4.30 g. Going through the results, it seems that the local mines were used to die-strike the coins. The obtained results are in good agreement with archaeological records

The composition of fluid inclusions in host minerals holds much information about the chemical environment of mineral formation. When solid inclusions are exposed through polishing, their content can readily be investigated with an electron or proton probe. However, with an electron probe, only the daughter minerals or the residue material left when a fluid inclusion is opened can be analyzed since electrons with energies of tens of keV cannot penetrate to the unexposed inclusion. On the other hand, proton beams of a few MeV can penetrate a few tens of μm of material and still be able to excite characteristic radiation. This phenomenon has been exploited for the analysis of subsurface inclusions. Ideally, standard petrographic sections are polished to that inclusions, targetted for analysis, are brought to within 10 μm of the surface. The overlying matrix reduces the sensitivity of PIXE for the elements of low Z such as Na and Al because of the attenuation of the X-rays. However, these elements, as well as elements of even lower Z, which cannot be analyzed with the electron probe, can readily be detected with PIGE at good sensitivity. (orig.)

Full text: The proton induced x-ray emission (PIXE) technique was used for analysis of trace elements in small quantities of biological samples. Both the biological samples of normal and cancer-afflicted human bladder tissues were studied. The present experiment was performed using a 3 MV pelletron accelerator at the Institute of Physics in Bhubaneswar, India. A proton beam of 3 MeV energy was used to excite the samples. NIST SRM 1577b Bovine Liver Tissue was used as external standards for the determination of trace element concentration in the biological tissue samples. The elements CI, K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn, and Se were identified and their concentrations were estimated. The concentrations of Ti and Zn are lower (p < 0.005) and that of Cr, Mn, Fe, Ni, and Cu are significantly higher (p < 0.001) in cancerous tissues than that in normal tissues. The deficiency or excess of different trace elements observed in the cancer tissues relative to the normal tissues of bladder are correlated to the pathology of cancer. (author)

Full Text Available The Montreal Definition and Classification divides Gastroesophageal Reflux Disease (GERD into esophageal symptomatic syndromes (and with mucosal damage and extraesophageal syndromes (with acid established association and proposed association. In typical GERD symptoms, an 8-week treatment with PPIs is satisfactory in most cases (> 90%. Response rates to PPIs in GERD are highly variable, as they also rely on an appropriate clinical diagnosis of the disease; endoscopy differentiates the macroscopic GERD phenotype. The non-erosive variety (50-70% prevalence has a different symptomatic response rate, as gastric acid is not the sole etiology of symptoms. The possible explanations of treatment failure include treatment adherence, PPI metabolism alterations and characteristics, and inadequate diagnosis. Refractory symptoms are related to gastric content neutralization by the chronic use of PPIs. Extraesophageal manifestations are associated with other pathophysiological mechanisms where an autonomic nervous system disturbance gives rise to symptoms. In these clinical entities, the relationship between symptoms and acid needs to be established in order to determine the use of PPIs, or consider other drugs. In other words, so as to "custom-tailor the best-fitting therapy" we need to answer the questions for whom, for what, how and for how long. Finally, PPI safety and tolerability are factors to be considered in elderly patients requiring chronic PPI use, who usually have chronic concomitant illnesses.La Clasificación de Montreal divide la enfermedad por reflujo gastro-esofágico (ERGE en síndromes esofágicos sintomáticos y con daño a la mucosa y en síndromes extraesofágicos con asociación establecida al ácido y asociación propuesta. En síntomas ERGE típicos el tratamiento con inhibidores de la bomba de protones (IBP es satisfactorio (> 90% a 8 semanas en la mayoría de los casos. Las tasas de respuesta a los IBP en la ERGE son muy variables

Highlights: • For the first time in Croatia, long term of fine aerosol pollution is reported. - Abstract: The results of a long term, multi elemental XRF and PIXE analysis of fine aerosol pollution in the city of Rijeka, Croatia, are reported for the first time. The samples were collected during a seven months period (6th Aug 2013–28th Feb 2014) on thin stretched Teflon filters and analyzed by energy dispersive X-ray fluorescence (EDXRF) at the Laboratory for Elemental Micro-Analysis (LEMA), University of Rijeka and by Particle Induced X-ray Emission (PIXE) using 1.6 MeV protons at the Laboratory for Ion Beam Interactions (LIBI), Ruđer Bošković Institute, Zagreb. The newly developed micro-XRF system at LEMA provided results for 19 elements in the range from Si to Pb. The PIXE at the LIBI provided information for the same elements as well for the light elements such as Na, Mg and Al. Black carbon was determined with the Laser Integrated Plate Method (LIPM). The results were statistically evaluated by means of the positive matrix factorization (PMF). The seven major pollution sources were identified together with their relative contributions, these are: secondary sulfates, road traffic, smoke, road dust, sea spray, ship emissions and soil dust.

Highlights: • For the first time in Croatia, long term of fine aerosol pollution is reported. - Abstract: The results of a long term, multi elemental XRF and PIXE analysis of fine aerosol pollution in the city of Rijeka, Croatia, are reported for the first time. The samples were collected during a seven months period (6th Aug 2013–28th Feb 2014) on thin stretched Teflon filters and analyzed by energy dispersive X-ray fluorescence (EDXRF) at the Laboratory for Elemental Micro-Analysis (LEMA), University of Rijeka and by Particle Induced X-ray Emission (PIXE) using 1.6 MeV protons at the Laboratory for Ion Beam Interactions (LIBI), Ruđer Bošković Institute, Zagreb. The newly developed micro-XRF system at LEMA provided results for 19 elements in the range from Si to Pb. The PIXE at the LIBI provided information for the same elements as well for the light elements such as Na, Mg and Al. Black carbon was determined with the Laser Integrated Plate Method (LIPM). The results were statistically evaluated by means of the positive matrix factorization (PMF). The seven major pollution sources were identified together with their relative contributions, these are: secondary sulfates, road traffic, smoke, road dust, sea spray, ship emissions and soil dust.

3D quantitative elemental maps of a section of a strand of hair were produced using a combination of PIXE-Tomography and simultaneous On/Off Axis STIM-Tomography at the University of Surrey Ion Beam Centre. The distributions of S, K, Cl, Ca, Fe and Zn were determined using the PIXE-T reconstruction package DISRA. The results were compared with conventional bulk PIXE analysis of tomographic data as determined using Dan32. The overall concentrations determined by PIXE were compared with elemental concentrations held in the University of Surrey Hair Database. All the entries currently in the database were produced using INAA. The merits and possible contributions of tomographic PIXE analysis to analysis of hair are discussed. The conclusions drawn from the PIXE-Tomography analysis can be used to argue for more stringent procedures for hair analysis at the University of Surrey. (author)

External-beam PIXE has been applied for the determination of the elemental composition of ancient Chinese bronze artifacts. Characteristic x-ray spectra from the samples bombarded with protons of 3 MeV have been measured with a HPGe detector. At each sample three spots were irradiated per run. Results of measurements on three fragments of bronze drinking vessels and helmet of Chinese ancient Chou and Shang dynasties (17th-8th century B.C.) are presented. To check the analytical method, we have also made measurements on the elemental composition of some modern coins. The results are discussed. (author)

Trace elements present in bottled mineral water have been studied by PIXE and ICP-MS. Samples from ten different brands of brands of bottled mineral water were prepared by preconcentration techniques. Measurements were carried out using the 2 MeV proton beam obtained from 3 MV Tandem pelletron accelerator at the Institute of Physics, Bhubaneswar. Our results are compared with Indian standard packaged natural mineral water specifications, World Health Organisation (WHO) and European guidelines for drinking water standards. Concentration of aluminum was found to be more in one of the brands. In general, our results are comparable to the above standards. (author)

Proton Induced X-ray Emission (PIXE) method is used for the determination of elemental concentrations in cancellous bone of human femoral head from five autopsies and seven patients with femoral neck broken. The specimen preparation and experimental procedure are described in detail. Using the t test, the results show that the concentrations of P, Ca, Fe, Cu, Sr in control group are higher than those in patient group, but the concentrations of S, K, Zn, Mn are not significantly different. The physiological functions of metallic elements in human bone are also discussed. (author). 19 refs., 1 fig., 4 tabs

A PIXE system has been developed for measuring trace element levels in biological samples and a study made of the precision and accuracy achievable. The calibration of the system has been established using thin targets of known elemental composition and the reproducibility studied using protons of energy 2.5 MeV. Both thick and thin samples prepared from NBS bovine liver have been analysed and the elemental ratios present established for a set of replicate samples. These are compared with the results of other workers. Problems relating to sample preparation are discussed.

External-beam PIXE has been applied for the determination of the elemental composition of ancient Chinese bronze artifacts. Characteristic x-ray spectra from the samples bombarded with protons of 3 MeV have been measured with a HPGe detector. At each sample three spots were irradiated per run. Results of measurements on three fragments of bronze drinking vessels and helmet of Chinese ancient Chou and Shang dynasties (17th-8th century B.C.) are presented. To check the analytical method, we have also made measurements on the elemental composition of some modern coins. The results are discussed. (author).

Enhanced X-ray yields from the metal components of homogeneous thick targets of binary metal fluorides were observed during PIXE irradiations with protons, deuterons and 3 He ions. The absence of these effects in the pure metals and in the corresponding metal oxides, nitrides and borides suggests that the fluoride component in such compounds plays a key role in producing the enhancement. Coulomb excitation of the extremely low-lying levels of the fluorine nucleus is discussed as a possible mechanism for the improved yields via secondary excitation. (orig.)

The use of animal teeth to replace human teeth in dentistry school classes and to test chemicals and fillings, motivated for a better characterization of the elementary composition of their enamel, since some of the chemical properties, adhesion and chemical compatibility may depend on these parameters. Cattle, swine and human teeth were collected by dentists of the University of Sao Paulo. These teeth came primarily from Sao Paulo region and were analyzed for trace elements at the Open Nuclear Physics Laboratory, using a high energy external proton beam, PIXE-PIGE setup

. (2007) [1] and Jiménez-Ramos et al. (2010) [2], radioactive particles from aircraft accidents in Palomares and Thule have been characterized. Using micro-Proton Induced X-ray Emission (μ-PIXE) and confocal X-ray fluorescence microprobe (μ-XRF), the L-lines of the main components in these particles, U......-lines present not overlapping between the main peaks in the spectra and the X-ray absorption in the sample is much lower than for L-lines....

Physical and chemical properties of the atmospheric aerosols is a fundamental to understand the behavior of aerosols in the atmosphere. The analysis of atmospheric aerosols is the most preferable fields of the PIXE. In this paper, the characteristics of atmospheric aerosols are reviewed at first, and the sampling method of atmospheric aerosols for the PIXE samples and the characterization of atmospheric aerosols using the PIXE analysis are discussed. (author)

The present work reports, the results of a first study of elemental composition in airborne particulate matter (in fine and coarse particle size fractions) collected at the Atmospheric Monitoring Station in the Municipality of Centro Habana, using the Particle-Induced X-ray Emission (PIXE) technique. At present, there is not information available about elements contents in airborne particulate matter from this region. For this study, we carried out a sampling campaign during five months (November 14, 2006 to April 19, 2007). The samples were collected every second day during 24 h under an air flux of 20 l/min. The air sampler used was a Gent Sampler equipped with a Stacked Filter Unit (SFU) system which allows the aerosol collection in both size fractions simultaneously. A total of 144 aerosol samples were collected (72 correspond to the fine mass particle and 72 to the coarse mass particle). For PIXE analysis, the samples were irradiated by 2.5 MeV energy protons from the 2MV Van de Graff Tandetron Accelerator from the Laboratory of PIXE analysis at ININ, Mexico. A total of 14 elements (S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Br and Pb) were consistently detected in both particle size fractions with minimum detection limits in the range of 1-10 ng/m3. The quantitative results obtained from PIXE elemental analysis for mass of particles in both fractions have revealed important information that has been used in a first attempt to understand and to characterize the atmospheric pollution of this area. A general discussion about these results is presented in this paper. (author)

The present work reports, the results of a first study of elemental composition in airborne particulate matter (in fine and coarse particle size fractions) collected at the Atmospheric Monitoring Station in the Municipality of Centro Habana, using the Particle-Induced X-ray Emission (PIXE) technique. At present, there is not information available about elements contents in airborne particulate matter from this region. For this study, we carried out a sampling campaign during five months (November 14, 2006 to April 19, 2007). The samples were collected every second day during 24 h under an air flux of 20 l/min. The air sampler used was a Gent Sampler equipped with a Stacked Filter Unit (SFU) system which allows the aerosol collection in both size fractions simultaneously. A total of 144 aerosol samples were collected (72 correspond to the fine mass particle and 72 to the coarse mass particle). For PIXE analysis, the samples were irradiated by 2.5 MeV energy protons from the 2MV Van de Graff Tandetron Accelerator from the Laboratory of PIXE analysis at ININ, Mexico. A total of 14 elements (S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Br and Pb) were consistently detected in both particle size fractions with minimum detection limits in the range of 1-10 ng/m3. The quantitative results obtained from PIXE elemental analysis for mass of particles in both fractions have revealed important information that has been used in a first attempt to understand and to characterize the atmospheric pollution of this area. A general discussion about these results is presented in this paper. (author)

In the corrosive environment of the mouth, a diversity of interactions take place at the solid-solid and solid-liquid interfaces of a tooth's filling. Moreover, the mineral elements of the restorative material may induce a complex response of the organism. The approach of these problems requires sensitive surface elemental analysis of the composite and of the dental enamel and dentine. Particle-induced X-ray emission (PIXE) is such a method and has been applied in investigations of hard dental tissues; however, it was not used so far in the study of dental composites. We continue our study by evaluating the potential of PIXE for analysis of these materials. Three types of composites with two color shades each have been studied. The measurements were performed with 3 MeV protons, using a hyperpure Ge detector in a spectroscopic chain connected to a computer. The spectra were processed with the dedicated program Leone. PIXE without additional Al absorbent foil allowed the detection of Z > 14 elements in composites. In two glass- and ceramics-based materials we found: Ca, Zr, Ba, Yb and traces of Sr and In in Tetric Ceram (Vivadent); and Ca, Zr, Ba, Hf, possibly Mn, and traces of Ni, Ho, Ti, Fe, Cr in Valux Plus (3M Dental), after elimination of the escape peaks. In quartz-based Evicrol (Spofa), Si, Ca, Ti, Fe and traces of K, Cr, Ni, Cu, Zn were seen. Materials with different color shades showed variations of Ti, Cr, Fe, Ni and Cu in Evicrol, as contrasted to Tetric Ceram and Valux Plus whose spectra were color-invariant. By its sensitivity and low background, PIXE enables the detection of many trace elements in dental composites; it could serve also in new materials' development and forensic expertise. (authors)

Dental composites made of silicates and oxides particles embedded in an organic polymer, show a dynamic evolution but are rather expensive. Recently, the Romanian biomaterial 'Restacril' offered a low-cost alternative. Because the durability of the composite dental fillings depends both on the main chemical composition and on the impurities that may influence the inorganic particles' properties and thus modifying the bio material clinical behaviour, the elemental analysis of the material is necessary for improving its quality. Particle-induced X-ray emission (PIXE), a sensitive method for multielemental trace detection widely used in biomedical applications, allowed us to evidence 21 mineral elements with Z > 14 in some commercial dental composites. Here we evaluate the performances of PIXE for the control of dental composites by carrying out qualitative analysis of three Romanian biomaterials. PIXE measurements on thick composite samples with a flat surface were done with 3 MeV protons at the NIPNE-HH (Horia Hulubei National Institute for Physics and Nuclear Engineering) tandem accelerator, using a hyper-pure Ge detector, 30 mm thick Al absorber foil and integration of beam current. Up to 21 elements with Z > 19 were detected: K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Ga, Sr, Zr, Nb, Ru, Ag, Ba, Yb, Nd, Hf, Au, As and Pb. The orders of magnitude of relative concentrations were evaluated using X-ray yields obtained for another light element thick composite target. The Romanian composites have specific and diverse compositions, containing a great number of minor and trace elements, many of whom are impurities. Use of higher purity raw materials is suggested to reduce the latter and improve the materials' quality. Refinement of X-ray yields by better matching matrixes calculations and use of concentration standards are proposed for quantitative PIXE analysis of the dental composites. (authors)

Micro-proton induced X-ray emission (micro-PIXE) method was applied to study the micro-localization of silver (Ag) in digestive glands of a terrestrial arthropod (Porcellio scaber) after feeding on silver nanoparticles (nano-Ag) dosed food. The aim of our work was to assess whether feeding on nano-Ag results in the assimilation of silver (Ag) in digestive gland cells. To study micro-localization and elemental distribution of Ag, the animals were fed on food dosed with nanoparticles for 14 days under controlled laboratory conditions. At the end of the feeding exposure, the animals were dissected and digestive glands prepared for micro-PIXE analyses and TEM investigation. The results obtained by micro-PIXE documented high amounts of Ag inside S-cells of the digestive gland epithelium; however, TEM investigation did not show particle aggregates inside digestive gland cells. Also no adverse effect on feeding behavior was recorded what is a measure of toxic effects. We explain the presence of Ag inside the cells as a result of the assimilation of dissoluted Ag ions from ingested nano-Ag particles. Assimilation of excessive amounts of ingested metal ions in S-cells is a well known metal detoxification mechanism in isopods. We discuss the advantages of using micro-PIXE for the micro-localization of elements in biological tissue in studies of interactions between nanoparticles and biological systems.

Technological characterization of pre-Hispanic gold metallurgy has still a wide deficit of analytical data. A set of 103 pieces from the so called “Quimbaya’s treasure” (QT) and the “Costa Rica collection” (CRC) of the Museo de America of Madrid were submitted to IBA analysis (PIXE and RBS) at the CMAM in three phases and the metal composition was determined. Only in a limited number of cases, due to the dramatic erosion of the gilded layer, produced by abrasive cleaning methods applied after the discovery and before the seventies, it was possible to determine also the sequence of layers, which gives information on the manufacture technology and the type and purity of the metals. PIXE results are reported and discussed. Data show that the CRC objects have very high gold levels (>80% in weight) while the QT have a more variable composition with significant Cu levels associated to the so called Tumbaga-alloy. In the cases where polishing had a tolerable effect, PIXE (and RBS), point to depletion gilding as a standard finishing process in the Costa Rica production, resulting in a gold rich surface alloy, while the variable composition of the QT objects may well be linked to deliberate colour choice.

Throughout this century, industrialized society has seriously affected the ecology by introducing huge amounts of pollutants into the atmosphere as well as marine and soil environments. On the other hand, it is known that these pollutants, in excess of certain levels of concentration, not only put at risk the life of living beings but may also cause the extinction of some species. It is therefore of basic importance to substantially increase quantitative determinations of trace element concentrations in biological specimens in order to assess the effects of pollutants. It is in this field that PIXE plays a key role in these studies, where its unique analytical properties are decisive. Moreover, since the importance of these research has been recognized in many countries, many scientists have been encouraged to continue or initiate new research programmes aimed to solve the worldwide pollution problem. This document presents an overview of those papers reporting the application of PIXE analysis to biological samples during this last decade of the 20th century and recounts the number of PIXE laboratories dedicating their efforts to find the clues of the biological effects of the presence of pollutants introduced in living beings. Sample preparation methods, different kinds of samples under study and the use of complementary analytical techniques are also illustrated. (author). 108 refs

Recently we completed a construction of a cryostat at Jožef Stefan Institute (JSI) nuclear microprobe enabling us to analyze various types of biological samples in frozen hydrated state using micro-PIXE/STIM/RBS. Sample load-lock system was added to our existing setup to enable us to quickly insert a sample holder with frozen hydrated tissue samples onto a cold goniometer head cooled with liquid nitrogen inside the measuring chamber. Cryotome-cut slices of frozen hydrated plant samples were mounted between two thin silicon nitride foils and then attached to the sample holder. Sufficient thermal contact between silicon nitride foils and sample holder must be achieved, as well as between the sample holder and the cold goniometer head inside the measuring chamber to prevent melting of the samples. Matrix composition of frozen hydrated tissue is consisted mostly of ice. Thinning of the sample as well as water evaporation during high vacuum and proton beam exposure was inspected by the measurements with RBS and STIM method simultaneously with micro-PIXE. For first measuring attempts a standard micro-PIXE configuration for tissue mapping was used with proton beam cross section of 1.2 × 1.2 μm 2 and a beam current of 100 pA. The temperature of the cold goniometer head was kept below 130 K throughout the entire proton beam exposure. First measurements of thin plant tissue samples in frozen hydrated state show minute sample degradation during the 10 h period of micro-PIXE measurements

In this paper, we demonstrate the ability of the Le-PIXE (Low Energy PIXE) technique, using proton energies < 1 MeV, for the monitoring of the thickness and the thickness uniformity of ultra thin (0.5 nm < t < 20 nm) chromium layers deposited onto quartz substrates. Chromium is a good candidate for obtaining conductive ultra thin layers on insulator substrates such as quartz (SiO2). The resistivity of such layers is highly related to the quality of the deposited chromium film. In order to optimize the deposition process, there is a need for rapid and accurate monitoring of such films (film thickness, thickness uniformity over a big surface...). The acquisition time needed to obtain results with less than 3-4 % precision was 5 minutes for the thinnest layers. The validation for the use of the Le-PIXE technique was checked by means of conventional RB S technique.

Elemental composition study of digestive cancer tissue with different localizations (esophagus, stomach, colon) by using PIXE analysis is presented. A number of 20 tumor and normal (control) tissue samples were analyzed. Thin targets were prepared by mineralization of the lyophilized tissue with nitric acid and dropping on 2 μm Mylar foil. The measurements were carried out in vacuum using 3 MeV protons delivered by the tandem accelerator in Bucharest, Romania. The following elements were identified: S, Cl, K, Ca, Cr, Mn, Fe, Cu and Zn. Although the results show relatively large variations from a sample to another there were obtained mean ratios of tumor/normal concentrations which are significantly greater than one, in the limit of the standard deviation for the following elements: K (1.45±0.28), Ca (1.30±0.21), Cr (2.33±0.56), and Zn (1.18±0.15). For the other determined elements, no significant difference between the tumor and normal tissues, in the limit of the present standard deviation, was found. (authors)

Elemental composition study of digestive cancer tissue with different localizations (esophagus, stomach, colon), by using PIXE analysis, is presented. A number of 20 tumors and normal (control) tissue samples was analyzed. Thin targets were prepared by mineralization with nitric acid of the lyophilized tissue and dropping on 2 μm Mylar foil. The measurements were carried out in vacuum using 3 MeV protons delivered by the Tandem Accelerator in Bucharest, Romania. The following elements were determined: S, Cl, K, Ca, Cr, Mn, Fe, Cu and Zn. Although the results show relatively large variations from a sample to another, there were obtained mean ratios of tumor/normal concentrations which are significantly greater than one, in the limit of the standard deviation, for the following elements: K(1.45 ± 0.28), Ca(1.30 ± 0.21), Cr(2.33 ± 0.56), and Zn(1.18 ± 0.15). For other elements determined, no significant difference between the tumor and normal tissues , in the limit of the present standard deviation, was found. (authors)

We have started PIXE research for environmental science at Van de Graaff accelerator facility in Tokyo Institute of Technology. Quantitative measurements of soluble fractions in river waters have been carried out using the preconcentrate method developed in Tohoku University. We reveal that this PIXE target preparation can be also applied to waste water samples. (author)

We have recently completed the construction of a new ion beamline primarily for particle-induced x-ray emission (PIXE) analysis. This will supplement our current ion microtomography (IMT) material characterization capabilities using accelerator microanalysis. In this paper we describe the PIXE beamline and give some results that characterize the system. We also report the results of some initial experiments

GridPix is a gas-filled detector with an aluminium mesh stretched 50 μm above the Timepix CMOS pixel chip. This defines a high electric field where gas amplification occurs. A feasibility study is ongoing at Nikhef for the application of the GridPix technology as a charge sensitive device in a dual

Full Text Available Aerosols play an important role in the atmosphere but are poorly characterized, particularly in urban areas like the Mexico City Metropolitan Area (MCMA. The chemical composition of urban particles must be known to assess their effects on the environment, and specific particulate emissions sources should be identified to establish effective pollution control standards. For these reasons, samples of particulate matter ≤2.5 μm (PM2.5 were collected during the MCMA-2003 Field Campaign for elemental and multivariate analyses. Proton-Induced X-ray Emission (PIXE, Proton-Elastic Scattering Analysis (PESA and Scanning Transmission Ion Microscopy (STIM measurements were done to determine concentrations of 19 elements from Na to Pb, hydrogen, and total mass, respectively. The most abundant elements from PIXE analysis were S, Si, K, Fe, Ca, and Al, while the major emissions sources associated with these elements were industry, wind-blown soil, and biomass burning. Wind trajectories suggest that metals associated with industrial emissions came from northern areas of the city whereas soil aerosols came from the southwest and increased in concentration during dry conditions. Elemental markers for fuel oil combustion, V and Ni, correlated with a large SO2 plume to suggest an anthropogenic, rather than volcanic, emissions source. By subtracting major components of soil and sulfates determined by PIXE analysis from STIM total mass measurements, we estimate that approximately 50% of non-volatile PM2.5 consisted of carbonaceous material.

Resorting to an external proton microbeam, PIXE analyses of three oil paintings on copper support dated from the XVII century and attributed to the Flemish artist Frans Francken II, were undertaken. The present work aims to contribute to the compositional study of the painting materials employed by XVII century artists that exploited copper as a support for oil painting, and specifically the materials used by Francken’s workshop, particularly copper plates. Because of the low thickness of the pictorial layers of this type of paintings and its non-destructive character, PIXE is the ideal technique to study the elemental composition of the paintings. Several spots in each painting were chosen for analysis in order to cover almost all the pigments used in the colour palette. Lead and calcium were detected in practically every analysed regions, probably related to the presence of lead white and chalk, usually used as ground layer on copper paintings. Small quantities of gold were also detected, which is present in many of this artist’s works to embellish some details of the representations. Also this work reports the first application of the external proton microbeam set-up available at CTN/IST in Portugal for the characterization of oil paintings

We have annually held an open experiment of PIXE analysis since 1996 to get people's understanding on nuclear technology and radiation science. Up to the present, more than 270 participants joined and enjoyed the open experiments. This year, we demonstrated performance of a submilli-PIXE camera and had sixty-nine participants in the open experiment of PIXE. Elemental spatial distribution images gave deep impression to the participants. Half of the participants were high school students since the open experiment of PIXE was held during the period of open campus of Tohoku University. About ten percents of the participants were junior high school students. Our open experiment of PIXE was very effective to arouse public interest in radiation science and nuclear technology. (author)

The elemental concentrations of Br, Ca, Ce, Cl, Co, Cr, Cs, F, Fe, Hf, K, Mg, Mn, Na, O, Rb, Sb, Sc, Se, V and Zn in 15 human lung autopsy samples, taken from subjects aged more than fifty years old, were determined by instrumental neutron activation analysis (INAA) using reactor neutrons in conjunction with a high resolution detection system. Two modes of irradiation and counting were applied; namely cyclic neutron activation analysis (CNAA) and conventional neutron activation analysis. Proton induced X-ray emission (PIXE) analysis, using a proton beam emerging from a 2 MV Van de Graaff accelerator, was additionally employed and Ge, Ni, P and Ti were also identified in the lung tissue. Detection of the X-ray spectra was performed using a high resolution Si(Li) semiconductor. The relevance of these results, including a comparison between the concentrations of elements measured in a pig's lung using CNAA and those found in the human lung is discussed. (author)

Ferromanganese nodules found on the Ocean bed are complex heterogeneous mixtures of several components. Two nodules from Central Indian Ocean Basin (CIOB) were analysed by proton induced X-ray emission (PIXE) technique using 3UD Tandem pelletron. The precision and the accuracy of this technique for chemical analyses has been confirmed by analysing USGS Geological Standards. Thick sample targets were bombarded by 3 MeV protons for the multielemental analysis. GUPIX-96 software was used for spectral data analysis. Quantitative estimate of K, Ca, Tl, V, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, As, Rb, Sr, Y, Zr, Mo, Ba, Ce, Tl and Pb has been ascertained. The occurrence of Ga, Ge, Rb and Zr in nodules from this region is reported for the first time. The role of manganese and iron oxide phases in determining the uptake of various trace elements from ocean water and bottom sediment pore water has been discussed. (author)

Hybanthus floribundus subsp. floribundus, a rare Australian Ni-hyperaccumulating shrub and Pityrogramma calomelanos var. austroamericana, an Australian naturalized As-hyperaccumulating fern are promising species for use in phytoremediation of contaminated sites. Micro-proton-induced X-ray emission (μ-PIXE) spectroscopy was used to map the elemental distribution of the accumulated metal(loid)s, Ca and K in leaf or pinnule tissues of the two plant species. Samples were prepared by two contrasting specimen preparation techniques: freeze-substitution in tetrahydrofuran (THF) and freeze-drying. The specimens were analysed to compare the suitability of each technique in preserving (i) the spatial elemental distribution and (ii) the tissue structure of the specimens. Further, the μ-PIXE results were compared with concentration of elements in the bulk tissue obtained by ICP-AES analysis. In H. floribundus subsp. floribundus, μ-PIXE analysis revealed Ni, Ca and K concentrations in freeze-dried leaf tissues were at par with bulk tissue concentrations. Elemental distribution maps illustrated that Ni was preferentially localised in the adaxial epidermal tissues (1% DW) and least concentration was found in spongy mesophyll tissues (0.53% DW). Conversely, elemental distribution maps of THF freeze-substituted tissues indicated significantly lower Ni, Ca and K concentrations than freeze-dried specimens and bulk tissue concentrations. Moreover, Ni concentrations were uniform across the whole specimen and no localisation was observed. In P. calomelanos var. austroamericana freeze-dried pinnule tissues, μ-PIXE revealed statistically similar As, Ca and K concentrations as compared to bulk tissue concentrations. Elemental distribution maps showed that As localisation was relatively uniform across the whole specimen. Once again, THF freeze-substituted tissues revealed a significant loss of As compared to freeze-dried specimens and the concentrations obtained by bulk tissue analysis

To control environmental pollution, a biodegradation technique involving a biomass is used to degrade the liquid wastes from certain industrial processes before disposal. (d, p) reactions were used to study the degradation process and the extent of removal of carbon and nitrogen. The PIXE-PIGME technique was used for the simultaneous study of the compositions of the biomass, the feed and the treated material. Measurements were obtained using protons of 2.5 MeV (for the the PIXE-PIGME measurements) and deuterons of 2.0 MeV using currents of the order of 25nA. The X-ray and γ-ray data were recorded simultaneously. Absolute concentrations were obtained by comparison with measurements of calibration standards. Results show that 54-58% of the carbon and 45-50% of the nitrogen is removed from the wastes and that the biomass is concentrating Cl, Ti, Ni and Fe. (author) 4 refs.; 8 figs

The application of the Particle Induced X-ray Emission (PIXE) technique to analyse quantitatively the elemental composition of hair specimens brings about some difficulties in the interpretation of the data. The present paper proposes a correction factor to account for the effects of the energy loss of the incident particle with penetration depth, and X-ray self-absorption when a particular geometrical distribution of elements in hair is assumed for calculational purposes. The correction factor has been applied to the analysis of hair contents Zn, Cu and Ca as a function of the energy of the incident particle. (orig.)

The application of the Particle Induced X-ray Emission (PIXE) technique to analyse quantitatively the elemental composition of hair specimens brings about some difficulties in the interpretation of the data. The present paper proposes a correction factor to account for the effects of energy loss of the incident particle with penetration depth, and x-ray self-absorption when a particular geometrical distribution of elements in hair is assumed for calculational purposes. The correction factor has been applied to the analysis of hair contents Zn, Cu and Ca as a function of the energy of the incident particle.(Author) [pt

A problem of the exact determination of the element concentration in different substances is of essential significance, especially in medical, biological, as well as environment protection investigations. For this purpose some chemical and physical methods are used such as very sensitive and precise techniques: PIXE and RBS. The main advantage of those methods is the sensitivity of ppm level and very small sample amount necessary for carrying out the investigations. In this article the investigation results obtained by PIXE and RBS methods for the metal contents in cow milk (18 various samples were studied) as well as the heavy metal admixtures in the brain of the living domestic animals (6 cows, 6 dogs and 17 rats) are presented. The samples were prepared for the analysis in a liofilization process, then they were mixed with spectral pure graphite. The PIXE and RBS investigations were performed using a proton beam of about 2 mm diameter, intensity of about 10 nA and energy of 2.5 MeV from the Van-de-Graaff generator, FLNP, JINR, Dubna. The measurements of the characteristic spectrum were carried out by means of a Si (Li) detector with the resolution of 200 eV at the energy of 6,4 keV. Generally, in all samples of milk and brain we could identify 20 elements, among them 13 (C, N, O, P, Cl, K, Ca, Fe, Cu, Zn. Br, Rb, Sr) appeared in all of the studied samples. The difference in the concentration of the most of those elements between samples was in the range of 15 - 20 %. This indicates a good accuracy of the used methods of measurement. Especially our attention was paid to the presence of Sr, Rb and Br, practically in all the milk samples. This fact requires further investigations. Such elements as Pb, As, Ni, Co, Mn, V and Ti were found in some samples, including all samples coming from regions of a high urbanization. It is characteristic that the milk samples coming from villages located considerably far-away from cities and from communication tracks, practically

In recent years, the self-sufficiency ratio of food in Japan has gradually decreased and 60% of foods are now imported from abroad. Japanese people rely strongly upon imported food and should take care of their safety, but what is happening now is that soil pollution in country of origin grows into a serious problem and can affect imported food. Umeboshi is one of the traditional pickled food in Japan and very popular. In the case of umeboshi, more than 65% of it is imported. We analyzed imported umeboshi and domestic ones by using in-air PIXE system and submili-PIXE camera at Tohoku University. In this experiment, the concentrations of toxic heavy metals such as As, Cd, Hg and Pb were lower than standard values given by a food hygiene law. Concentrations of elements heavier than Ca show similar trend among each sample. On the other hand, lighter elements than Ca show large differences, which is related to food coloring or processing technique. (author)

We have developed an analysis system based on the pattern analysis method. By testing the system, several difficulties of the present method have been identified. We found the following solutions for them: pre-selection of candidate elements in a sample and the use of a proper absorber. The pre-selection of the candidate elements will not be a serious drawback in the industrial PIXE, because it will be easy to pre-process the spectra for a few samples in the beginning of the mass processing of samples of the same kind. On the other hand, reduction of the efficiency due to the use of funny filter is significant only in the lower energy region, where we usually do not suffer from insufficient yields of lighter elements in common samples. The selection of the most suitable filter requires PIXE user to be deeply experienced. In particular, it is not easy to choose the best filter to suppress the yield of peak of an abundant element as the absorption edge filter. It will be important task to find a set of suitable combination of representative samples and corresponding filters. Furthermore, the peak profile model should be improved from the simple Gaussian approximation to more realistic ones with exponential tail, flat component below the peak and escape peaks, etc. It is also necessary to develop a theoretical approach for the background shape of the bremsstrahlung. (J.P.N.)

Particle induced X-ray emission (PIXE) and nuclear microprobe (NMP) have been used in an exploratory work to study elemental alterations in tissues of experimental animals submitted to osteoporosis preventive treatments. Osteopathologies have been associated with several factors, such as hormonal disturbances, metabolic aberrations, low dietary Ca and vitamin D intake, excess of iron, among other possible factors. Hormonal treatments seem to be beneficial to the incorporation of Ca in bone but breast and endometrial cancers constitute significant side effects that cannot be ignored. Wistar female rats were used to test the effect of estrogen therapy in osteoporosis progression. The variations of elemental concentrations in uterus and the Ca content of femoral bones of ovariectomised rats under estrogen therapy were investigated. PIXE, Rutherford backscattering spectrometry and secondary electron microscopy techniques were applied for the characterisation of biological materials, with respect to morphology and trace element distribution determination. The increase of Ca and Fe concentrations in uterus and the variations for Ca distribution patterns in bone of rats submitted to estrogen therapy were the major features observed

In labor environment, the quantity of chemical substances in the air is more, and their kinds are more diversified than in general home environment. It has been well known that some substances contained in the aerosol in labor environment (floating dust in the atmosphere) such as asbestos and hexavalent chromium have the possibility of causing serious injuries such as cancer of respiratory organ. In order to identify the harmful substances to which laborers are exposed and to take the measures for removing them, it is necessary to investigate in detail into many factors related to the effect of aerosol on human bodies, such as the composition of elements, chemical condition, concentration, the particle size of dust and temporal and spatial distributions. For the purpose, sampling and analysis must be carried out so that information can be extracted as much as possible from a minute amount of sample. The particle induced x-ray emission (PIXE) analysis is very effective for this application. In this paper, the development of a PIXE analysis system and the knowledge obtained by the sampling and measurement of aerosol in indoor labor environment are reported. The labor environment selected is that of the workshop of Department of Liberal Arts, University of Tokyo. Sampling, the experimental apparatus, the method of data analysis and the results of analysis are described. (Kako, I.)

Full Text Available Small GTPases function as molecular switches in cell signaling, alternating between an inactive, GDP-bound state, and active GTP-bound state. βPix is one of guanine nucleotide exchange factors (GEFs that catalyze the exchange of bound GDP for ambient GTP. The central goal of this review article is to summarize recent findings on βPix and the role it plays in kidney pathology and physiology. Recent studies shed new light on several key questions concerning the signaling mechanisms mediated by βPix. This manuscript provides a review of the various mechanisms whereby βPix has been shown to function within the kidney through a wide range of actions. Both canonical GEF activity and non-canonical signaling pathways mediated by βPix are discussed. Distribution patterns of βPix in the kidney will be also covered. Much has yet to be discerned, but it is clear that βPix plays a significant role in the kidney.

In-air PIXE was used to analyze trace elements in otoliths from several species of teleost fish in order to examine the correlation between the trace elements concentrations and environmental conditions. Mn, Fe, Zn and Sr were detected accurately in the order of ppm by using the in-air PIXE. It seemed that concentrations of Sr and Zn in red sea bream otoliths increased in proportion to higher seawater temperature. In addition, there were significant differences in trace element composition between that of reared red sea bream and rockfish and that of wild ones. Preliminary results indicate that the PIXE is a powerful technique to investigate fish otoliths. (author)

A 3-step extraction procedure was developed to allow particle-induced X-ray emission (PIXE) analysis of particulate matter in normal glass fibre filter samples. The detection limits, expressed in ng/m 3 of air, for the filter extracts were 5 to 30 times lower than those achieved by PIXE analysis or ordinary Nuclepore polycarbonate filter samples. The concentration results were compared with those obtained from routine atomic absorption spectrometry measurements and with the PIXE data from Nuclepore stacked filter unit samples taken in parallel. (orig.)

This paper reports the PIXE study on the provenance of Chinese ancient porcelain made in 7-10th century. The chemical compositions of Jun celadon samples made at Juntai, Linru and Hunyuan kilns, the white-glazed porcelain samples made at Ding, Huangye and Dangyangyu kilns, and the Ru celadon samples made at Qiangliang Temple were measured by external-beam PIXE, and the factor analysis was applied for identifying their provenances. Experimental results show that the porcelain products made at different kilns can be distinguished according to the compositional differences measured by PIXE

This paper reports the PIXE study on the provenance of Chinese ancient porcelain made in 7-10th century. The chemical compositions of Jun celadon samples made at Juntai, Linru and Hunyuan kilns, the white-glazed porcelain samples made at Ding, Huangye and Dangyangyu kilns, and the Ru celadon samples made at Qiangliang Temple were measured by external-beam PIXE, and the factor analysis was applied for identifying their provenances. Experimental results show that the porcelain products made at different kilns can be distinguished according to the compositional differences measured by PIXE.

This paper reports the PIXE study on the provenance of Chinese ancient porcelain made in 7-10th century. The chemical compositions of Jun celadon samples made at Juntai, Linru and Hunyuan kilns, the white-glazed porcelain samples made at Ding, Huangye and Dangyangyu kilns, and the Ru celadon samples made at Qiangliang Temple were measured by external-beam PIXE, and the factor analysis was applied for identifying their provenances. Experimental results show that the porcelain products made at different kilns can be distinguished according to the compositional differences measured by PIXE.

We summarize some of the information about the nucleon-nucleon force which has been obtained by comparing recent calculations of proton-proton bremsstrahlung with cross section and analyzing power data from the new TRIUMF bremsstrahlung experiment. Some comments are made as to how these results can be extended to neutron-proton bremsstrahlung. (Author) 17 refs., 6 figs

Despite of ongoing progress in the biochemistry of phytopharmaceutical drugs, their mineral micro- and trace elements have not been studied in detail. These elements may have therapeutic or toxic activity which should be assessed by sensitive investigations. The latter can be done by multielemental analysis with nuclear and atomic methods. We previously found 28 elements in some Romanian plant drugs by nuclear activation analysis. The availability of this method is, however, limited by the access to a nuclear reactor. Particle-induced X-ray emission (PIXE) is an alternative method with high performances in biomedicine and requiring no sample preparation for drugs' studies. We applied PIXE in the qualitative analysis of three plant drugs - Liv52, Mentat, and Geriforte - used as invigorators, protectors and prophylactics in oxidative stress diseases. Measurements with 3 MeV protons at the 8.5 MV NIPNE-HH (Horia Hulubei National Institute for Physics and Nuclear Engineering) tandem accelerator, using a hyper-pure Ge detector and no additional absorber foil, evidenced unusually complex elemental compositions of drugs. Up to 31 elements with Z > 15 were found: P, S, Cl, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Br, Rb, Sr, Y, Zr, Cs, Ba, La, Ce, Pr, Nd, Sm, Eu, Hg, and As and/or Pb, from major to trace levels. The three drugs' qualitative composition were found to be rather similar. Relative concentrations were well evaluated with X-ray yields calculated for another kind of light element thick target. Drug's toxic elements - As and/or Pb, Hg, and possibly Ga - were all at trace levels, but their accumulation might be harmful. Some essential elements like K, Ca, Cr, Fe, Cu, Zn, Br, Rb, Sr can be biologically useful. X-ray yields improvement and other ways for PIXE quantitative analysis of the phytotherapeutic drugs are outlined. (authors)

The most important technical aspects of a new experimental method projected for the study of the p-nucleus interactions are exposed. The energy distributions of the protons, deuterons, tritium, helium-3 and alpha particles produced in the p-Al interactions at 19'8 QeV/c are shown. Ours results are compared with the predictions of the evaporation model. (Author) 14 refs.

The most important technical aspects of a new experimental method projected for the study of the p-nucleus interactions are exposed. The energy distributions of the protons, deuterons, tritium, helium-3 and alpha particles produced in the p-Al interactions at 19'8 QeV/c are shown. Ours results are compared with the predictions of the evaporation model. (Author) 14 refs.

The work on trace element analysis using proton induced X-ray emission technique (PIXE) with the proton beam from 5.5 MeV Van de Graaff accelerator at Trombay, is described. The experimental set up consisted of an indigeneously built 220 eV resolution Si(Li) x-ray spectrometer and target chamber having arrangements to mount upto twelve targets. In the present work, a variety of samples of biological nature, monazite mineral and some other samples were analyzed along with a standard multi-element sample. The sample preparation technique for different samples is also given in the report. For quantitative estimation of trace elements, a computer code developed earlier was used. The proton induced x-ray spectra of various samples and their computer fits are presented and quantitative results for some selected samples are also given. The minimum detection limits which were achieved with the present set up are also given. (auth.)

Natural corundum, one of the most important exports of Thailand, is a rare, durable and valuable gemstone. The value of these precious stones is determined by their visual appearances, including brilliance, color, fire (light dispersion) and luster. Corundum is an allochromatic mineral whose trace element concentration depends on the origin and has influence on price setting. This work attempts to use an alternative method to identify the geological deposits of rubies and sapphires found in the Thai market which came from various countries, e.g., Africa, Cambodia, Myanmar, Sri Lanka, Thailand and USA. Interrelations between most important major trace elements are the main results of this work. Quantitative analysis of trace elements were performed by particle-induced X-ray emission (PIXE) technique, using 2-MeV proton beam generated and accelerated by the 1.7 MV tandem accelerator at Chiang Mai University. The trace elements of interest are Ti, Cr, Fe and Ga. We have found that the relationships between the ratios of trace element concentration can be used to classify the deposit type. Moreover, this method shows a clear separation between two main types of geological deposits, basaltic and metamorphic deposits, which further helps in determining the gemstone origin. For example, the gemstones from Cambodia, Thailand and the USA can be classified as the basaltic deposits with their high concentration in Fe but low in Ti, while the gemstones from Africa, Myanmar and Sri Lanka are metamorphic deposits because they have low Fe but high Ti concentrations. Both deposits required plots of pairs of trace elements and their ratios in population field appearance in order to distinguish their origins. The advantageous of these methods appear to be a new and a sustainable procedure for determining gemstone origins

Natural corundum, one of the most important exports of Thailand, is a rare, durable and valuable gemstone. The value of these precious stones is determined by their visual appearances, including brilliance, color, fire (light dispersion) and luster. Corundum is an allochromatic mineral whose trace element concentration depends on the origin and has influence on price setting. This work attempts to use an alternative method to identify the geological deposits of rubies and sapphires found in the Thai market which came from various countries, e.g., Africa, Cambodia, Myanmar, Sri Lanka, Thailand and USA. Interrelations between most important major trace elements are the main results of this work. Quantitative analysis of trace elements were performed by particle-induced X-ray emission (PIXE) technique, using 2-MeV proton beam generated and accelerated by the 1.7 MV tandem accelerator at Chiang Mai University. The trace elements of interest are Ti, Cr, Fe and Ga. We have found that the relationships between the ratios of trace element concentration can be used to classify the deposit type. Moreover, this method shows a clear separation between two main types of geological deposits, basaltic and metamorphic deposits, which further helps in determining the gemstone origin. For example, the gemstones from Cambodia, Thailand and the USA can be classified as the basaltic deposits with their high concentration in Fe but low in Ti, while the gemstones from Africa, Myanmar and Sri Lanka are metamorphic deposits because they have low Fe but high Ti concentrations. Both deposits required plots of pairs of trace elements and their ratios in population field appearance in order to distinguish their origins. The advantageous of these methods appear to be a new and a sustainable procedure for determining gemstone origins.

Natural corundum, one of the most important exports of Thailand, is a rare, durable and valuable gemstone. The value of these precious stones is determined by their visual appearances, including brilliance, color, fire (light dispersion) and luster. Corundum is an allochromatic mineral whose trace element concentration depends on the origin and has influence on price setting. This work attempts to use an alternative method to identify the geological deposits of rubies and sapphires found in the Thai market which came from various countries, e.g., Africa, Cambodia, Myanmar, Sri Lanka, Thailand and USA. Interrelations between most important major trace elements are the main results of this work. Quantitative analysis of trace elements were performed by particle-induced X-ray emission (PIXE) technique, using 2-MeV proton beam generated and accelerated by the 1.7 MV tandem accelerator at Chiang Mai University. The trace elements of interest are Ti, Cr, Fe and Ga. We have found that the relationships between the ratios of trace element concentration can be used to classify the deposit type. Moreover, this method shows a clear separation between two main types of geological deposits, basaltic and metamorphic deposits, which further helps in determining the gemstone origin. For example, the gemstones from Cambodia, Thailand and the USA can be classified as the basaltic deposits with their high concentration in Fe but low in Ti, while the gemstones from Africa, Myanmar and Sri Lanka are metamorphic deposits because they have low Fe but high Ti concentrations. Both deposits required plots of pairs of trace elements and their ratios in population field appearance in order to distinguish their origins. The advantageous of these methods appear to be a new and a sustainable procedure for determining gemstone origins.

To fully utilise the multielement capability and short measurement time of PIXE it is desirable to have an automated computer evaluation of the measured spectra. Because of the complex nature of PIXE spectra, a critical step in the analysis is the data reduction, in which the areas of characteristic peaks in the spectrum are evaluated. In this package the computer program BATTY is presented for such an analysis. The second step is to determine element concentrations, knowing the characteristic peak areas in the spectrum. This requires a knowledge of the expected X-ray yield for that element in the sample. The computer program THICK provides that information for both thick and thin PIXE samples. Together, these programs form the package PIXAN used at Lucas Heights for PIXE analysis

The hoards of metallic objects belonging to the Late European Bronze Age can be interpreted differently depending on the type, number and composition of the artefacts. PIXE analysis has been performed in nine items from the Hoard of Freixanda in Portugal comprising four socket axes, a palstave axe, a ring, a chisel, a dagger, and a casting debris. Besides the composition of the main matrix elements, that is Cu and Sn, the amount of trace elements of interest like, As, Pb, Ni, and Ag has been determined using this ion beam technique. The high tin content alloy and the high purity of the metals from the Freixanda hoard are characteristic of the Portuguese and Spanish Late Bronze Age metallurgy, supporting the idea of a regional production.

The Thai amulets that created in an image of Lord Buddha meditation were made to explain the Dharma of Buddha and believed to bless every life in this world for good karma. Phra Somdej Wat Rakhang amulet is the top of the five most famous Thai amulets. There are many molds with various compositions. In this work, it was the first time that X-ray fluorescence spectrometry methods; scanning electron microscope cooperated with energy dispersive X-ray fluorescence spectrometer (SEM/EDS) and particle induced X-ray emission spectroscopy (PIXE) were carried out to analyze their compositions. Two samples were collected from different molds. Results revealed C, Ca and Si were main composition. The differences in their compositions have been used to identify and characterize for each molds

Full text: University of Surrey has, for the past four years, collaborated with police institutions from across Europe and the rest of the world lo scope potential applications of ion beam analysis (IBA) in forensic science. In doing this we have consulted practitioners across a range of forensic disciplines, and critically compared IBA with conventional characterisation techniques to investigate the areas in which IBA can add evidential value. In this talk, the results of this feasibility study will be presented, showing the types of sample for which IBA shows considerable promise. We will show how a combination of PIXE with other IBA techniques (EBS, PIGE, MeV-SIMS) can be used to give unprecedented characterisation of forensic samples and comment on the significance of these results for forensic casework. We will also show cases where IBA not appear to add any significant improvement over conventional techniques. (author)

The REX code and subsequent HEX code, originating at Florida State University, have been extensively used for PIXE spectra fitting. In 1989 we produce a renovated HEX package: WITS-HEX, enabling the original Fortran program to be more accessible to the PIXE community. We modernised the user interface by replacing the batch mode of operation with an integrated, menu-driven environment. We added the ability to edit support data files from within the program, provided detailed feedback during the fitting process and enhanced spectral plots using high resolution colour graphics. Our prototype also permitted the inclusion of many more peaks and absorption coefficients into the element library than the original HEX, permitting a more extensive element request list to be used during the fitting operation. We have now completed the second phase of the renewal of HEX. The man-machine interface has been upgraded to conform to the IBM SAA Common User Access (CUA) standard. This eliminated several of the sequential (modal) human-computer dialogues, replacing them with a single parallel system. The support utility used in WITS-HEX to convert the binary format of spectra captured using foreign data acquisition systems has been replaced by code to directly access data in ASCII format. The program is now equipped with context-sensitive help and a tutorial. The polynomial background mode has been supplemented by a digital filter model, eliminating the associated instability from the fitting process and other spectral features modelled. The program has been validated by comparing results with those obtained from the former versions: WITS-HEX and HEX. A demonstration version is available on request for evaluation purposes. (orig.)

Human kidney stones were analyzed by PIXE and RBS techniques using 2 MeV He ++ beam. The stones were found to contain the elements: C, N, O, F, Na, Mg, Si, P, S, Cl, K, Ca, Fe and Br. Results obtained by PIXE agree with the results obtained by RBS within experimental errors. A Mechanism for the formation of the kidney stones is suggested. 3 figs., 1 tab

Fish otoliths are continuously deposited from fish birth to its death along with encoding environmental information. In order to decode the information, PIXE was adopted as trace elemental analysis of the otoliths. Strontium to calcium concentration ratios of red sea bream otoliths varied among rearing stations. The Sr/Ca ratios of Lake Biwa catfishes also varied between male and female and among fishing grounds. The PIXE analysis was applied to the fish stock discrimination. (author)

Some examples are given for unriddling of ancient-medieval culture by PIXE. Effectiveness of PIXE to analyze art and archaeological objects is also explained. Objects employed here are 1) red, yellow, blue and white pigments painted on sun-dried bricks excavated in Egypt, 2) ancient glass beads used in the Near East, 3) South American mummy hair, 4) ancient slag excavated from Kansai-district, Japan 5) ink used by Galileo Galilei and 6) Renaissance style enameled gold jewelry. (author)

Particle Induced X-ray Emission (PIXE), an accelerator based analytical technique has been employed in this work for the analysis of trace elements in the cancerous and non-cancerous tissues of rectal cancer patients. A beam of 3 MeV protons generated from 3 MV Pelletron accelerator at the Ion Beam Laboratory of Institute of Physics, Bhubaneswar, India was used as projectile to excite the atoms present in the tissues samples. PIXE technique, with its capability to detect simultaneously several elements present at very low concentrations, offers an excellent tool for trace element analysis. The characteristic X-rays emitted by the samples were recorded by a high resolution Si (Li) detector. On the basis of the PIXE spectrum obtained for each sample, the elements Cl, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, and Br were identified and their relative concentrations were estimated in the cancerous and non-cancerous tissues of rectum. The levels of Mn, Fe, Co, Cu, Zn, and As were higher (p < 0.005) while the levels of Ca, Cr and Ni were lower (p < 0.005) in the cancer tissues relative to the normal tissues. The alterations in the levels of the trace elements observed in the present work are discussed in this paper with respect to their potential role in the initiation, promotion and inhibition of cancer of the rectum.

Proton induced X-ray emission (PIXE) technique is an effective method for the chemical composition analysis of ancient glass samples without destruction. Chemical composition of the ancient glass samples dated from the Warring States Period (770-476 B.C.) to the Six Dynasties Period (220-589 A.D.), which were unearthed in Sichuan area, was quantitatively determined by the PIXE technique. The results show that the glass Bi (disc) and the glass eye beads of the Warring States Period all belong to the PbO-BaO-SiO 2 system. According to the composition and shape, we infer that these glass Bi and eye beads were made in China. Whereas, the chemical compositions of the glass ear pendants and beads of the Six Dynasties Period are varied, including K 2 O-CaO-SiO 2 , K 2 O-SiO 2 and other glass systems, Based on the obtained results and those from literatures, some questions related to the technical propagation of the ancient Chinese glass are discussed. (authors)

PIGE and PIXE techniques were employed to the study of elemental constituents of some traditional medicinal plants generally used in curing many diseases and ailments in South-Western Nigeria. Analysis were also carried out on commonly edible vegetables of medicinal and pharmacological importance. PIGE measurements were carried out using 3.5 MeV collimated protons from the 7 MV CN Van-de-Graaff accelerator of INFN, LNL, Legnaro (Padova), Italy, while the PIXE measurements were carried out using 1.8 MeV from the 2.5 MV AN 2000 Van-de-Graaff accelerator of the same laboratory. The results show that many of the medicinal plants contain elements of cardinal importance in man's metabolism. The results from the vegetables also show that presence of vital elements that are needed for growth and developments. In addition, some of the toxic elements which include arsenic, cadmium, mercury, etc. were not detected. However, some of the recipes contain trace amounts of lead at very low concentrations. This calls for proper control of dose rates in some samples to prevent the attendant negative cumulative effects. (author). 17 refs, 1 fig., 5 tabs

The PIXE technique was employed for the study of Esie museum stone sculptures using 2.55 MeV protons from the 3 MeV tandem accelerator (NEC 3 UDH) in Lund, coupled with the geological and archaeological findings. The aim is to elucidate and decipher the prodigious but rather enigmatic and bewildering stone sculptures. PIXE results show that the composition of the stone sculptures are 40.69% talc-tremolite schist, 30.88% talc-chlorite schist, 15.20% talc-tremolite-anthophyllite schist and 13.24% talc-amphibolite schist. Thus the composition of Esie sculptures are found to be the same with the locally available talc-schists present around Esie. The geological evidence (mineralogical results) corroborated this as there was no textural or mineralogical difference between the talc-bearing country rock (outcrop) in Esie and the museum soapstone samples studied. Consequently, there is a very high probability that the sculptures were carved using the locally available talc-schists. (author). 7 refs, 4 figs, 2 tabs

In order to examine whether a trace-element analysis by PIXE (Particle Induced X-ray Emission) gives a clue to identify production area of agricultural products, we carried out a study on soy beans as an example. In the present study, a proton beam at the energy of 2.3MeV was provided by Van de Graaff accelerator at Osaka University. We used a Ge detector with Be window to measure X-ray spectra. We prepared sample soy beans from China, Thailand, Taiwan, and 7 different areas in Japan. As a result of PIXE analysis, 5 elements, potassium, iron, zinc, arsenic and rubidium, have been identified. There are clear differences in relative amount of trace-elements between samples from different international regions. Chinese beans contain much more Rb than the others, while there are significant differences in Fe and Zn between beans of Thailand and Taiwan. There are relatively smaller differences among Japanese beans. This result shows that trace-elements bring us some practical information of the region where the product grown.

Remediation of metal-contaminated soils and waters poses a challenging problem due to its implications in the environment and the human health. The use of metal-accumulating plants to remove toxic metals, including Cd, from soil and aqueous streams has been proposed as a possible solution to this problem. The process of using plants for environmental restoration is termed phytoremediation. Cd is a particularly favourable target metal for this technology because it is readily transported and accumulated in the shoots of several plant species. This paper investigates the sites of metal localization within Arabidopsis thaliana leaves, when plants are grown in a cadmium-rich environment, by making use of nuclear microscopy techniques. Micro-PIXE, RBS and SEM analyses were performed on the scanning proton microprobe at the CNA in Seville (Spain), showing that cadmium is sequestered within the trichomes on the leaf surface. Additionally, regular PIXE analyses were performed on samples prepared by an acid digestion method in order to assess the metal accumulation of such plants.

Micro-proton-induced X-ray emission (micro-PIXE) was used to map the distribution of several nutritionally important minerals found in the grain tissue of two cultivars of pearl millet (Pennisetum glaucum (L.) R. Br.). The distribution maps revealed that the predominant localisation of minerals was within the germ (consisting of the scutellum and embryo) and the outer grain layers (specifically the pericarp and aleurone); whilst the bulk of the endosperm tissue featured relatively low concentrations of the surveyed minerals. Within the germ, the scutellum was revealed as a major storage tissue for P and K, whilst Ca, Mn and Zn were more prominent within the embryo. Fe was revealed to have a distinctive distribution pattern, confined to the dorsal end of the scutellum; but was also highly concentrated in the outer grain layers. Interestingly, the hilar region was also revealed as a site of high accumulation of minerals, particularly for S, Ca, Mn, Fe and Zn, which may be part of a defensive strategy against infection or damage. Differences between the two cultivars, in terms of the bulk Fe and P content obtained via inductively coupled plasma optical emission spectrometry (ICP-OES), concurred with the average concentration data determined from the analysis of micro-PIXE spectra specifically extracted from the endosperm tissue.

Calcium hydroxide is used in dentistry and generally shows a clinically acceptable biocompatibility. However various commercial assortments show differences in their clinical performances, suggesting that certain aspects of their action are not completely understood and pointing to the necessity of new investigation methods. We report a preliminary study on two types of calcium hydroxide products carried out by thick target PIXE with 3.0 MeV protons, aiming to assess the potential of this method for the analysis of such biomaterials used in endodontic dentistry. (Semi)quantitative analysis was performed by use of reference materials, and relative concentrations of elements with respect to Ca were determined with an accuracy of about 30%; tentative absolute concentrations were also estimated by using Ca as a reference element. In both formulations, a number of trace elements (Mn, Fe, Zn and Sr, and possibly Cu and Pb - probably impurities from the raw materials) were evidenced. These trace elements together with the Ba/Ca ratio are reliable fingerprints for the identification of the materials, and evidenced a different origin for the Ca(OH) 2 used in the two specimens. Possible applications of PIXE in dental research may bring relevant compositional insight, and further studies of such materials are suggested. (authors)

A set of silver-copper coins were investigated for their stochiometry in order to check any possible counterfeit. The studied coins are 50 Lebanese Piastres and are relatively recent, minted in 1952. They are supposed to have nominal concentration of 60 wt.% Ag and 40 wt.% Cu. In this work, it is shown the utility and capability of combining PIXE (particle induced X-ray emission) and RBS (Rutherford backscattering spectrometry) techniques to determine the elemental content and check the presence, if any, of surface layer. For this aim, 3 MeV proton beam and Al funny filter, used as x-ray absorber, were used to determine the elemental composition, based on the emission and detection of the characteristic x-rays of the corresponding elements. The first PIXE results of the supposed bulky coins showed an excess of silver composition vs. copper. In addition, the experimental protocol was checked by analyzing some other coins of known composition, such as 1-euro and 2-euro coins.

By utilising targeted microprobe technology, the analysis of elements incorporated within the hard bio-mineralised structures of marine organisms has provided unique insights into the population biology of many species. As hard structures grow, elements from surrounding waters are incorporated effectively providing a natural 'tag' that is often unique to the animal's particular location or habitat. The spatial distribution of elements within octopus stylets was investigated, using the nuclear microprobe, to assess their potential for determining dispersal and population structure in octopus populations. Proton Induced X-ray Emission (PIXE) was conducted using the Dynamic Analysis method and GeoPIXE software package, which produced high resolution, quantitative elemental maps of whole stylet cross-sections. Ten elements were detected within the stylets which were heterogeneously distributed throughout the microstructure. Although Ca decreased towards the section edge, this trend was consistent between individuals and remained homogeneous in the inner region of the stylet, and thus appears a suitable internal standard for future microprobe analyses. Additional analyses used to investigate the general composition of the stylet structure suggested that they are amorphous and largely organic, however, there was some evidence of phosphatic mineralisation. In conclusion, this study indicates that stylets are suitable for targeted elemental analysis, although this is currently limited to the inner hatch region of the microstructure.

By utilising targeted microprobe technology, the analysis of elements incorporated within the hard bio-mineralised structures of marine organisms has provided unique insights into the population biology of many species. As hard structures grow, elements from surrounding waters are incorporated effectively providing a natural 'tag' that is often unique to the animal's particular location or habitat. The spatial distribution of elements within octopus stylets was investigated, using the nuclear microprobe, to assess their potential for determining dispersal and population structure in octopus populations. Proton Induced X-ray Emission (PIXE) was conducted using the Dynamic Analysis method and GeoPIXE software package, which produced high resolution, quantitative elemental maps of whole stylet cross-sections. Ten elements were detected within the stylets which were heterogeneously distributed throughout the microstructure. Although Ca decreased towards the section edge, this trend was consistent between individuals and remained homogeneous in the inner region of the stylet, and thus appears a suitable internal standard for future microprobe analyses. Additional analyses used to investigate the general composition of the stylet structure suggested that they are amorphous and largely organic, however, there was some evidence of phosphatic mineralisation. In conclusion, this study indicates that stylets are suitable for targeted elemental analysis, although this is currently limited to the inner hatch region of the microstructure

The impact of coal-burning emission on sulfur in camphor leaves was investigated using Proton Induced X-ray Emission (PIXE) and synchrotron radiation technique X-ray Absorption Near-Edge Structure (XANES) spectroscopy. The PIXE results show that the sulfur concentrations in the leaves collected at the polluted site are significantly higher than those in controls. The sulfur XANES spectra show the presence of organic (disulfides, thiols, thioethers, sulfonates and sulfoxides) and inorganic sulfur (sulfates) in the leaves. The inorganic sulfur in the leaves of camphor tree polluted by coal combustion is 15% more than that of the control site. The results suggest that the long-term coal-burning pollution resulted in an enhanced content of the total sulfur and sulfate in the leaves, and the uptake of sulfur by leaves had exceeded the metabolic requirement of plants and the excess of sulfur was stored as SO{sub 4}2{sup -}. It can monitor the sulfur pollution in atmosphere.

To investigate the cause of Alzheimer`s disease (senile dementia of Alzheimer`s disease type), we examined aluminium (Al) in the brain (hippocampus) of patients with Alzheimer`s disease using heavy ion (5 MeV Si{sup 3+}) microprobe particle-induced X-ray emission (PIXE) analysis. Heavy ion microprobes (3 MeV Si{sup 2+}) have several times higher sensitivity for Al detection than 2 MeV proton microprobes. We also examined Al in the brain of these patients by energy dispersive X-ray spectroscopy (EDX). (1) Al was detected in the cell nuclei isolated from the brain of patients with Alzheimer`s disease using 5 MeV Si{sup 3+} microprobe PIXE analysis, and EDX analysis. (2) EDX analysis demonstrated high levels of Al in the nucleolus of nerve cells in frozen sections prepared from the brain of these patients. Our results support the theory that Alzheimer`s disease is caused by accumulation of Al in the nuclei of brain cells. (author)

Modern sunscreens contain particles like TiO 2 having sizes of 25-70 nm and acting as a reflecting substance. For cosmetic reasons the particle size is minimized. Questions have been raised to what degree these nano particles penetrate the skin barrier, and how they do affect the human. The EU funded project 'Quality of skin as a barrier to ultra-fine particles' - NANODERM has started with the purpose to evaluate the possible risks of TiO 2 penetration into vital skin layers. The purpose of the work presented here was to find the optimal conditions for micro-PIXE analysis of Ti in thin skin sections. In the skin region where Ti is expected to be found, the naturally occurring major elements phosphorus, chlorine, sulphur and potassium have steep gradients and thus influence the X-ray background in a non-predictable manner. Based on experimental studies of Ti-exposed human skin sections using proton energies ranging from 1.8-2.55 MeV, the corresponding PIXE detection limits for Ti were calculated. The energy that was found to be the most favourable, 1.9 MeV, was then selected for future studies

This study reports the work developed in the Ion Implantation Laboratory (Porto Alegre, RS, Brazil) in order to implement the micro-NRA technique for the study of light elements in organic tissues. In particular, the work was focused on nuclear reactions employing protons and alphas with carbon. The (p,p) resonances at 0.475 and 1.734 were investigated. The (α,α) resonance at 4.265 MeV was studied as well. The results indicate that the yields for the 0.475 and 1.734 MeV resonances are similar. Elemental maps of different structures obtained with the micro-NRA technique using the 1.734 MeV resonance were compared with those obtained with micro-PIXE employing a SDD detector equipped with an ultra-thin window. The results show that the use of micro-NRA for carbon at 1.734 MeV resonance provides good results in some cases at the expense of longer beam times. On the other hand, micro-PIXE provides enhanced yields but is limited to surface analysis since soft X-rays are greatly attenuated by matter

Proton induced X-ray and γ-ray emission (PIXE/PIGE) have been used to analyze major and trace elements in a suite of 140 core samples from around of the Jim's Find South gold anomaly in the Tanami desert, located in heavily weathered terrain. Simultaneous analyses were obtained for 30 elements, ranging in atomic number from 3 Li to 90 Th. The method was chosen because of its speed and the wide range of determination, its flexibility, precision and low detection limits. The regolith powder samples were treated by hot aqua regia before making them into pills. The PIXE/PIGE data of the acid insoluble residue give three factor analysis clusters. The first cluster comprises the elements F, Al, K, V, Mn, Fe, Ga, Rb, W and Au and is essentially related to sericitic wallrock alteration. The second cluster consists of Ti, As, Y, Zr, and Nb and is largely related to resistant minerals. The third cluster consists of Na, Ca and Sr and is interpreted to comprise elements in weatherable minerals such as feldspar and thus represents weathering intensity. While the Rb/K ratio and the product of As x Cu x Ni provide the best surface expression of the gold mineralisation, the Rb/AI ratio provides the best expression of the sericitic alteration around the ore body

The proton magnetic resonance spectroscopy is a technique of metabolic Imaging allowing in vivo measurement of the levels of different metabolites. Is under increasing development and has shown an improvement of diagnostic indexes and therapeutic, since it allows: differential diagnosis between injuries, determination of tumor grade of Pre surgical form, determination of the presence of a lesion until it is clear, definition of progress and evaluation of the effects of a treatment. The aim in this work is to have a mannequin that allows analyze and adjust various parameters involved in the spectroscopic process, and establish a quantification of these parameters. (Author)

Pigments and paint materials are known to be sensitive to particle irradiation. Occasionally, the analysis of paintings by PIXE can induce a slight or dark stain depending on the experimental conditions (beam current, dose, particle energy). In order to understand this discoloration, we have irradiated various types of art white pigments – lead white (hydrocerussite and basic lead sulfate), gypsum, calcite, zinc oxide and titanium oxide – with an external 3 MeV proton micro-beam commonly used for PIXE experiments. We have observed various sensitivities depending on the pigment. No visible change occurs for calcite and titanium oxide, whereas lead white pigments are very sensitive. For the majority of the studied compounds, the discoloration is proportional to the beam current and charge. The damage induced by proton beam irradiation in lead white pigments was studied by micro-Raman and XPS spectroscopies. Structural modifications and dehydration were detected. Damage recovery was investigated by thermal treatment and UV-light irradiation. The discoloration disappeared after one week of UV illumination, showing that PIXE experiments could be safely undertaken for pigments and paintings

Metal fiducial markers are often implanted on the back of the eye before proton therapy to improve target localization and reduce patient setup errors. We aim to detect characteristic x-ray emissions from metal targets during proton therapy to verify the treatment range accuracy. Initially gold was chosen for its biocompatibility properties. Proton-induced x-ray emissions (PIXE) from a 15 mm diameter gold marker were detected at different penetration depths of a 59 MeV proton beam at the CATANA proton facility at INFN-LNS (Italy). The Monte Carlo code Geant4 was used to reproduce the experiment and to investigate the effect of different size markers, materials, and the response to both mono-energetic and fully modulated beams. The intensity of the emitted x-rays decreases with decreasing proton energy and thus decreases with depth. If we assume the range to be the depth at which the dose is reduced to 10% of its maximum value and we define the residual range as the distance between the marker and the range of the beam, then the minimum residual range which can be detected with 95% confidence level is the depth at which the PIXE peak is equal to 1.96 σbkg, which is the standard variation of the background noise. With our system and experimental setup this value is 3 mm, when 20 GyE are delivered to a gold marker of 15 mm diameter. Results from silver are more promising. Even when a 5 mm diameter silver marker is placed at a depth equal to the range, the PIXE peak is 2.1 σbkg. Although these quantitative results are dependent on the experimental setup used in this research study, they demonstrate that the real-time analysis of the PIXE emitted by fiducial metal markers can be used to derive beam range. Further analysis are needed to demonstrate the feasibility of the technique in a clinical setup.

Proton induced X-ray emission (PIXE) technique is used for analysis of trace elements present in the blood sera of ovarian cancer patients and healthy controls. This work is also intended to establish the role played by trace elements in carcinogenic process. It is observed that the concentrations of elements Ti, V, Cr, Mn, Fe, Ni, Rb and Sr are lower and the concentration of Cu is higher in the cancer patients when compared to controls. However, no change in concentration is found in the elements Co, Zn, As, Se and Br. Correlation analysis of the data using SPSS 16.0 has revealed a strong positive correlation between Ti-V, Ni-Co, Cu-Fe, As-Ti, Br-Ti, Br-V and Sr-Fe while strong negative correlations are observed for Cu-Ti, As-Cu and Br-Cu. Changes in trace elemental content are probably associated with ovarian carcinogenesis. (author)

In this work, we describe the compositional analysis performed by scanning-mode PIXE on the metal threads of a XIII century embroidery. The precious work analysed is the pillow-case used to cover the pillow, on which - according to tradition - St. Francis of Assisi was resting his head when he died. Measurements were performed in order to characterise the embroideries of the two sides and the passementerie in the lateral hems. Several areas, each of the order of two square millimetres, were scanned with a 3 MeV proton external beam of 20 {mu}m size on target, using the external micro-beam facility of our laboratory, with list-mode acquisition. Analysis of elemental maps and spectra from selected homogeneous sub-areas allowed us to extract the quantitative composition of the gilded tape and estimates of its thickness.

In this work, we describe the compositional analysis performed by scanning-mode PIXE on the metal threads of a XIII century embroidery. The precious work analysed is the pillow-case used to cover the pillow, on which - according to tradition - St. Francis of Assisi was resting his head when he died. Measurements were performed in order to characterise the embroideries of the two sides and the passementerie in the lateral hems. Several areas, each of the order of two square millimetres, were scanned with a 3 MeV proton external beam of 20 μm size on target, using the external micro-beam facility of our laboratory, with list-mode acquisition. Analysis of elemental maps and spectra from selected homogeneous sub-areas allowed us to extract the quantitative composition of the gilded tape and estimates of its thickness

In this work, we describe the compositional analysis performed by scanning-mode PIXE on the metal threads of a XIII century embroidery. The precious work analysed is the pillow-case used to cover the pillow, on which - according to tradition - St. Francis of Assisi was resting his head when he died. Measurements were performed in order to characterise the embroideries of the two sides and the passementerie in the lateral hems. Several areas, each of the order of two square millimetres, were scanned with a 3 MeV proton external beam of 20 μm size on target, using the external micro-beam facility of our laboratory, with list-mode acquisition. Analysis of elemental maps and spectra from selected homogeneous sub-areas allowed us to extract the quantitative composition of the gilded tape and estimates of its thickness.

Micro-proton-induced X-ray emission ({mu}-PIXE) analysis has been employed in investigating the presence of number of essential anions and cations in thin sections of diseased human articular cartilage affected by osteoarthritis (OA). Distribution maps for Ca, P, K and S in diseased sections show marked alterations in the concentrations of these at the bone-cartilage interface compared to normal tissue. For a decalcified section of human articular cartilage, organisational changes of the collagen network were investigated by small-angle X-ray scattering (SAXS). The established gradual reorientation of collagen fibres from vertical to the surface of the joint to normal to the bone-cartilage interface is observed to be heavily disrupted in OA.

Micro-proton-induced X-ray emission (μ-PIXE) analysis has been employed in investigating the presence of number of essential anions and cations in thin sections of diseased human articular cartilage affected by osteoarthritis (OA). Distribution maps for Ca, P, K and S in diseased sections show marked alterations in the concentrations of these at the bone-cartilage interface compared to normal tissue. For a decalcified section of human articular cartilage, organisational changes of the collagen network were investigated by small-angle X-ray scattering (SAXS). The established gradual reorientation of collagen fibres from vertical to the surface of the joint to normal to the bone-cartilage interface is observed to be heavily disrupted in OA.

External muPIXE has been used for characterisation of small samples of varnish from historical violins, and pieces of varnished wood from historical and modern stringed instruments. To obtain spatially resolved information about the distribution of elements across the varnish layers single-spot analysis, line-scans, and area-mapping were performed. Local resolution of approximately 20 mum was obtained from the 3 MeV, 1 nA proton micro-probe. Results from simultaneous multi-element determination of Na, Mg, Al, Si, P, S, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Br, Rb, Sr, Ag, Cd, Sn, Ba, and Pb in historical varnishes are presented. Semi-quantitative evaluation of line-scans recorded on diverse historical varnishes is reported. The applied method is discussed in detail and the results obtained are critically reviewed and compared with those in the literature.

Minute fragments from nine gold nuggets from Transylvania - two belonging to placer deposits and seven to primary deposits - were analyzed by PIXE and PIGE at the AGLAE tandem accelerator of the Centre de Recherche et de Restauration des Musees de France (C2RMF) with a 3 MeV proton beam extracted into air. This study was triggered by some archaeological provenance issues for which the elemental characterization of the Transylvanian gold source, exploited from the Antiquity, was required. All analyzed Transylvanian gold nuggets are characterized by a consistently high amount of Ag (18% on average). Au and Ag add up to roughly 99%, the other elements - Cu, Fe, Te, Pb - being detected only at a trace level. The obtained results are in good agreement with the previous analyses of Transylvanian gold

Otoliths are biogenic, carbonate concretions which form part of the hearing/balance system in fishes. The radial growth of otoliths and the variation of trace elements along the radius appear to capture important aspects of fishes' environmental history. At the Lund Nuclear Microprobe Laboratory, we have begun to use Proton-Induced X-ray Emission spectroscopy (PIXE) for micro-elemental analysis of otoliths. The experimental procedure is discussed and a number of examples of what can be investigated are presented. In particular, movement of diadromous species (eel, menhaden, and anadromous brown trout) can be detected between fresh and brackish water by Sr/Ca ratio. This technique has also been used to identify fish that were raised in freshwater hatcheries and then released to brackish water (pike-perch example)

Anguilla japonica has a high economic value. The abundance had decreased significantly due to excessive fishing and change in the aquatic ecology. Life history patterns of A. japonica have been studied to prevent excessive fishing and make management plans. Strontium (Sr)-calcium (Ca) ratio along a line down the long axis from the core to the edge of the yellow eel's otolith was measured using micro proton induced X-ray emission (micro-PIXE). An efficient and precise method was proposed to locate the core where an otolith begins to grow, based on Sr concentration and distribution. Using this method, life history patterns of the yellow eels collected from Jingjiang River in China were investigated. In general, there are two types, river eels and estuarine eels.

Anguilla japonica has a high economic value. The abundance had decreased significantly due to excessive fishing and change in the aquatic ecology. Life history patterns of A. japonica have been studied to prevent excessive fishing and make management plans. Strontium (Sr)-calcium (Ca) ratio along a line down the long axis from the core to the edge of the yellow eel's otolith was measured using micro proton induced X-ray emission (micro-PIXE). An efficient and precise method was proposed to locate the core where an otolith begins to grow, based on Sr concentration and distribution. Using this method, life history patterns of the yellow eels collected from Jingjiang River in China were investigated. In general, there are two types, river eels and estuarine eels.

Proton Induced X-Ray Emission (PIXE) and Neutron Activation Analysis (NAA) have emerged as powerful analytical techniques for the detection of trace elements in environmental samples, especially in the antarctic environmental, because of its multielemental character and high sensitivity. This methods of analysis have been used to find the concentration of trace elements in the lichens collected from Antarctica zone. Trace contents of elements like As, Au, Ba, Br, Ca, Ce, Cl, Co, Cr, Cs, Cu, Eu, Fe, Hf, Hg, K, La, Mn, Na, Ni, Rb, S, Sb, Se, Sm, Sr, Ti, Tb, Th, U, Zn and Yb have been determined. Preliminary data suggest that nuclear methods may be useful in elucidating element absorption and transport mechanisms in lichens as a sensitive indicator of the species growing in the environmental polluted sites. (authors)

Red layered medieval stained glass windows on a transparent greenish substrate are characteristic of European medieval cathedrals, but few compositional analyses have been performed on the coloured layers. The PIXE technique has been performed on a red layered stained glass window obtained during the restoration works carried out in Las Huelgas Monastery in Burgos (Spain). Protons of 3 MeV with a beam of 4 x 5 {mu}m{sup 2} were used to acquire elemental maps of a cross section of the sample, in order to observe the homogeneity of the layered structure and its substrate. In our work, copper was detected as in other layered glasses but a correspondence with lower amounts of zinc has also been determined. Both elements appear enriched in the red coloured layers, while the other quantified elements have the same relative composition along the sample. Corrosion layers, due to the lead supporting structure of the window, were also found.

Suspended particles in a street canyon were investigated by collecting air particulate matter on thin filters at heigths 2.3 to 20.5 m. The weather parameters and traffic characteristics were registered during the collection. Quantitative analysis of 15 trace elements from AI to Pb was carried out by the PIXE method using 1.8-2.0 MeV protons. The concentration of lead was found to decrease exponentially when going from street level to roof level. Almost all the trace elements analyzed were found to fall into two groups with different vertical distributions. The collected matter above 10 m height was found to be due mainly to combustion originated motor vehicle exhaust, the matter below 10 m to soil originated dust. (orig.)

We have used particle induced X-ray emission (PIXE) to analyze the elemental compositions and uptakes of a lanthanide, yttrium in this report, in tumors and normal tissues of nude mice. A small amount of yttrium nitrate was injected into nude mice with tumors. Samples of normal and malignant tissues taken from these mice were bombarded by the 2 MeV proton beam from a 3 MeV Van de Graaff accelerator with a Ge detector system to determine the relative elemental compositions of tissues and the relative concentrations of yttrium taken up by these tissues. We found that the uptakes of yttrium by tumors were at least five times more than those by normal tissues. Substantial differences were often observed between the trace element weight (or concentration) pattern of the cancerous and normal tissues. The present result is compared with human tissues.

Suillus luteus/Pinus sylvestris mycorrhizas, collected from zinc wastes in Southern Poland, were selected as potential biofilters on the basis of earlier studies carried out with energy dispersive spectrometry (EDS) microanalytical system coupled to scanning electron microscope (SEM) and transmission electron microscope (TEM). Using the National Accelerator Centre (NAC) nuclear microprobe, elemental concentrations in the ectomycorrhiza parts were for the first time estimated quantitatively. Micro-proton-induced X-ray emission (PIXE) true elemental maps from freeze-dried and chemically fixed mycorrhizas revealed strong accumulation of Ca, Fe, Zn and Pb within the fungal mantle and in the rhizomorph. Vascular tissue was enriched with P, S and K, while high concentrations of Si and Cl were present in the endodermis. Cu was the only element showing elevated concentrations in the cortex region. Elemental losses and redistributions were found in mycorrhizas prepared by chemical fixation. Some problems related to elemental imaging are discussed.

Suillus luteus/Pinus sylvestris mycorrhizas, collected from zinc wastes in Southern Poland, were selected as potential biofilters on the basis of earlier studies carried out with energy dispersive spectrometry (EDS) microanalytical system coupled to scanning electron microscope (SEM) and transmission electron microscope (TEM). Using the National Accelerator Centre (NAC) nuclear microprobe, elemental concentrations in the ectomycorrhiza parts were for the first time estimated quantitatively. Micro-proton-induced X-ray emission (PIXE) true elemental maps from freeze-dried and chemically fixed mycorrhizas revealed strong accumulation of Ca, Fe, Zn and Pb within the fungal mantle and in the rhizomorph. Vascular tissue was enriched with P, S and K, while high concentrations of Si and Cl were present in the endodermis. Cu was the only element showing elevated concentrations in the cortex region. Elemental losses and redistributions were found in mycorrhizas prepared by chemical fixation. Some problems related to elemental imaging are discussed

Trace elemental analysis was carried out in various parts of some anti-diabetic medicinal plants using PIXE technique. A 3 MeV proton beam was used to excite the samples. The elements Cl, K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn, Br, Rb and Sr were identified and their concentrations were estimated. The results of the present study provide justification for the usage of these medicinal plants in the treatment of diabetes mellitus (DM) since they are found to contain appreciable amounts of the elements K, Ca, Cr, Mn, Cu, and Zn, which are responsible for potentiating insulin action. Our results show that the analyzed medicinal plants can be considered as potential sources for providing a reasonable amount of the required elements other than diet to the patients of DM. Moreover, these results can be used to set new standards for prescribing the dosage of the herbal drugs prepared from these plant materials

Elemental analysis of Fenugreek medicinal plant collected from different regions was carried out by Proton Induced X-ray Emission (PIXE) and Inductively Coupled Plasma Mass Spectroscopy (ICP-MS) techniques. The elements Li, Be, Al, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br, Rb, Sr, Ag, Cd, Ba, Pb and U were identified and their concentrations were estimated. These elements were found to be in widely varying concentrations in the analyzed Fenugreek medicinal plant collected from different regions. of the. The results of the present study provide a better understanding of the pharmacological action of Fenugreek medicinal plant and it can also be used to set new standards for prescribing the dosage of herbal drugs. (author)

A newly constructed chamber for measuring with MeV proton beams at small incidence angles (0 to 35 mrad) is used to analyse trace elements on flat surfaces such as Si wafers, quartz substrates and perspex. This set-up is constructed in such a way that the X-ray detector can reach very large solid angles, larger than 1 sr. Using these large solid angles in combination with the reduction of bremsstrahlungs background, lower limits of detection (LOD) using TPIXE can be obtained as compared with PIXE in the conventional geometry. Standard solutions are used to determine the LODs obtainable with TPIXE in the optimized set-up. These solutions contain traces of As and Sr with concentrations down to 20 ppb in an insulin solution. The limits of detection found are compared with earlier ones obtained with TPIXE in a non optimized set-up and with TXRF results. (author)

Organic ligand with carboxyhydrazide functional group was immobilised on the surface of silica gel and the metal binding capacity of the ligand-embedded silica was investigated. The functional group was covalently bonded to the silica matrix through a spacer of methylene groups by sequential reactions of silica gel with dibromobutane, malonic ester and hydrazine in different media. Surface area value of the modified silica was determined. The changes in surface area were correlated with the structural change of the silica surface due to chemical modifications. A mixture solution of metal ions [K(I),Cr(III),Co(II),Ni(II),Cu(II),Zn(II),Hg(II) and U(VI)] was treated with the ligand-embedded silica in 10(-3) M aqueous solution. The measurement of metal extraction capacity of the silica based ligand was done by multielemental analysis of the metal complexes thus formed by using Proton Induced X-ray Emission (PIXE) technique.

Archaeological research on trade and exchange systems in Melanesia has been advanced by the application of chemical analysis to artefacts and their raw materials. Using the measurement of proton induced X-rays (PIXE) and gamma rays (PIGME), in an automated system, it has been possible to chemically characterise over 2000 obsidian specimens for up to 21 elements. The data analysis has shown that discrimination is possible between source sub-units within a related volcanic suite of sources. The source groups, and the artefacts belonging to them, can be quickly and confidently sorted by applying multivariate clustering and allocation procedures to the data. This work has also shown that obsidian was carried from sources to sites more than 400 km away, across a sea barrier, around 6000 years ago and more than 3000 km from the Bismark Archipelage to Vanuatu (New Hebrides) between 3000-4000 years ago.

Due to the interactions occurring at the solid-solid and solid-liquid interfaces of a tooth's filling, the mineral elements of the restorative composite may induce a complex response of the organism. To study such problems, sensitive surface trace element analysis is required. Particle-induced X-ray emission (PIXE) has a detection limit one order of magnitude lower than XRF and has been used for hard dental tissues, but not yet for dental composites. We evaluated the potential of PIXE in a study of ten types of composites used in restorative dentistry, some of them with two color shades each. The samples were prepared as described for XRF. The measurements were performed with 3 MeV protons from a van de Graaff tandem linear accelerator, using a hyper pure Ge detector and collecting the spectra for 1.5-4 hours. The spectra were processed with the program Leone. The proton route in the sample calculated with the Trim program (∼ 50-100 μm) exceeded the size of mineral particles (0.02-30 μm), thus granularity did not affect the analysis. The PIXE analysis detected Z ≥ 19 elements in all composites, and Z≥14 elements in only one low Z material. PIXE detected generally the same dominant elements, but many more trace elements than XRF. Thus both Charisma (Kulzer) and Pekafill (Bayer) contained Ba as the major element, but trace elements were Ni, Zn, In, in the first, and Fe, Cu, Zn, Sr, Ag in the second. In other glass- and ceramics-based materials we found: Ca, Zr, Ba, Yb and traces of Sr, In, and possibly Ti in Tetric Ceram and in Ariston (both from Vivadent); Ca, Zr, Ba, Hf, possibly Mn, and traces of Ni, Ho, Ti, Fe, Cr in Valux Plus (3M Dental); Sr, Ba (major), K, Fe, Mn (minor), and traces of Ni, Zn, In, in F2000 Compomer (3M Dental); Ba (major) and traces of Fe, Ni, Sr in Surefil (Dentsply). In quartz-based materials we detected: Si, Ca, Ti, Fe and traces of K, Cl, Cr, Ni, Cu, Zn in Evicrol (Spofa); low and trace levels of Ca, Ti, Cr, Mn, Fe, Cu in

Trace elements play an important role in a number of biological processes. Astaxanthin, a carotoid pigment found in certain marine plant and animals, has shown anti cancer and anti free radical properties. This work intended to understand the effect of Astaxanthin in breast cancer (invasive ductal carcinoma) by using micro-PIXE method. For this aim the concentration of trace elements were compared in healthy, cancerous and cancer treated with astaxanthin in the breast and liver tissues of breast cancer bearing mice, using proton induced X-ray emission. Materials and Methods: Proton induced X-ray emission was used In a study intending to compare the concentration of trace elements in breast and liver tissues of mice bearing tumor, three groups of mice: healthy, cancerous, and cancerous treated by astaxanthin, were considered. Astaxanthin was supplied from Research Institute of women, Alzahra University. Results: Comparing the untreated tumor tissue, treatment with Astaxanthm significantly decreased the amount Fe, P, S, and Ca elements level in tumor tissue of the breast cancer. It is also found that the concentrations of those elements in liver of the untreated mice and the liver of treated mice with astaxanthin were fairly equal. Astaxanthln significantly decrease the accumulation of elements in the site of tumor, and caused the breast cancer cell membrane to lose their desire to collect the elements from healthy tissues. Conclusion: The micro -PIXE technique could calculate elemental concentrations in tissues. Changes in metallic elements may affect microenvironment and cell functions, which might led lead to cell degeneration or death, the results shows that astaxanthin reduces vital element concentration in tumor site, thus it could be used as an anti tumor agent.

A method combining proton-induced X-ray emission spectrometry (PIXE) and Rutherford backscattering spectrometry (RBS) was used to determine the composition of 61 porcelain shards from the Yuan Dynasty (1271-1368 A.D.) unearthed from the Waguantan kiln site at Tianzhu County in Guizhou Province, China. Based on our previous experimental setup, an electron gun device with a LaB6 crystal cathode was installed to solve the problem created when the incident proton beams generated electric charge accumulations on the surfaces of the insulating porcelain samples, which induced a large bremsstrahlung background. The use of the electron gun has largely eliminated the large bremsstrahlung background and has therefore improved the detection limits for elements, especially for trace elements, and made it possible to determine the origin of the porcelains based on the trace elements. Major and trace elemental compositions of the porcelain bodies and glazes measured by PIXE and RBS were analyzed by the factor analysis method. The factor analysis showed that a few pieces of porcelain with a style similar to the porcelain of the Longquan kiln among the unearthed porcelains from the Waguantan kiln site did not have obvious differences in elemental compositions from other remaining porcelains unearthed from the Waguantan kiln site, indicating that the pieces of unearthed porcelain with the Longquan kiln style did in fact belong to the product fired locally by imitating the model of the Longquan celadon with local raw materials. This result therefore indicated that the Longquan kiln technology that originated from the Five Dynasties (907-960 A.D.) had been propagated to the Waguantan kiln site of Guizhou Province in the Yuan Dynasty.

This study is the first national attempt to assess the levels of PMs in Beirut city and consequently understand air pollution distribution. Aerosol sampling was carried out using three PM{sub 10} and three PM{sub 2.5} samplers which were installed at three locations lying along the SE-NW direction over Beirut. The sampling of PM{sub 10} and PM{sub 2.5} was done during a period extending from May till December 2009. The random collection of the particles (1 in 6 days) was carried out on Teflon filters, for a period of 24-h. The elemental analysis of particulate matter was performed using proton induced X-ray emission technique PIXE at the Lebanese 1.7 MV Tandem-Pelletron accelerator of Beirut. Na, Mg, Al, Si, P, S and Cl were quantified using 1 MeV proton beam, while K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn and Pb were determined using 3 MeV-energy of proton beam.

The flavin chromophore in blue light using FAD (BLUF) photoreceptors is surrounded by a hydrogen bond network that senses and responds to changes in the electronic structure of the flavin on the ultrafast time scale. The hydrogen bond network includes a strictly conserved Tyr residue, and previously we explored the role of this residue, Y21, in the photoactivation mechanism of the BLUF protein AppA by the introduction of fluorotyrosine (F-Tyr) analogs that modulated the pKa and reduction potential of Y21 by 3.5 pH units and 200 mV, respectively. Although little impact on the forward (dark to light adapted form) photoreaction was observed, the change in Y21 pKa led to a 4,000-fold increase in the rate of dark state recovery. In the present work we have extended these studies to the BLUF protein PixD, where, in contrast to AppA, modulation in the Tyr (Y8) pKa has a profound impact on the forward photoreaction. In particular, a decrease in Y8 pKa by 2 or more pH units prevents formation of a stable light state, consistent with a photoactivation mechanism that involves proton transfer or proton coupled electron transfer from Y8 to the electronically excited FAD. Conversely, the effect of pKa on the rate of dark recovery is markedly reduced in PixD. These observations highlight very significant differences between the photocycles of PixD and AppA, despite their sharing highly conserved FAD binding architectures.

The flavin chromophore in blue light using FAD (BLUF) photoreceptors is surrounded by a hydrogen bond network that senses and responds to changes in the electronic structure of the flavin on the ultrafast time scale. The hydrogen bond network includes a strictly conserved Tyr residue, and previously we explored the role of this residue, Y21, in the photoactivation mechanism of the BLUF protein AppA by the introduction of fluorotyrosine (F-Tyr) analogs that modulated the pKa and reduction potential of Y21 by 3.5 pH units and 200 mV, respectively. Although little impact on the forward (dark to light adapted form) photoreaction was observed, the change in Y21 pKa led to a 4,000-fold increase in the rate of dark state recovery. In the present work we have extended these studies to the BLUF protein PixD, where, in contrast to AppA, modulation in the Tyr (Y8) pKa has a profound impact on the forward photoreaction. In particular, a decrease in Y8 pKa by 2 or more pH units prevents formation of a stable light state, consistent with a photoactivation mechanism that involves proton transfer or proton coupled electron transfer from Y8 to the electronically excited FAD. Conversely, the effect of pKa on the rate of dark recovery is markedly reduced in PixD. These observations highlight very significant differences between the photocycles of PixD and AppA, despite their sharing highly conserved FAD binding architectures.

Trace elements in a Japanese subterranean xylophagous termite, Coptotermes formosanus Shiraki, were analyzed by the PIXE method. The total amount of the 14 predominant elements out of 27 detected in an intact termite was higher in a soldier termite (23 000 {mu}g/g) than in a worker termite (10 000 {mu}g/g). A block of wood (Pinus densiflora Sieb. et Zucc.) for termite feed had a much lower concentration (3600 {mu}g/g) compared with that in an intact termite. This probably relates the functional bio-condensation and/or bio-recycling of trace elements in C. formosanus. When a termite was separated into three anatomical parts, head, degutted body and gut, the worker gut contained the highest total amount of the 14 predominant measured elements (31 000 {mu}g/g). This might be correlated with the higher activity of food digestion and energy production in the worker gut. Moreover, the mandible of the soldier head, with an exoskeleton that is intensely hardened, showed a preferential distribution of Mn and Fe. These results suggest that the characteristic localization of elements will be closely related to the functional role of the individual anatomical part of C. formosanus.

Particle-induced X-ray emission (PIXE) analysis of the lighter elements in time-resolved air particulate deposits has been carried out. Minimum detection limits have been determined for 1.0, 2.0 and 3.5 MeV protons. Quantitative PIXE analysis results, obtained with 2 MeV protons, are given for temporal variations in the elemental concentrations of Na, Al, Si, S, Cl, K, Ca and Fe. Rutherford backscattering (RBS) spectra were taken simultaneously with the PIXE spectra to provide information on lead concentrations and deposit thicknesses. The experimental problems associated with the quantitative analysis of light elements on cellulose acetate filters are described. The relationship between these results and meteorological data is discussed. (author)

Proton induced X-ray emission (PIXE) technique has been used for identification and quantitative analysis of the elemental concentration in thick bread samples. Bread samples were air-oven dried at 60degC and milled in a clean agate mortar to homogenize the sample and pressed into a pellet. PIXE technique relies on the analysis of the energy spectra of the characteristic X-ray emitted from the thick bread sample and the orchard leaf standard (NIST-SRM-1571) bombarded with 2.0 MeV protons. The concentration of the elements (Cl, K, Ca, Mn, Fe, Cu, and Zn) in the bread samples was determined by comparison with NIST orchard leaf standard. The accuracy of the measurements ranged between ±2% and ±10% for the most elements detected in this method. The aim of this study is to establish the reference concentration of trace elements in the Iraqi bread using PIXE technique. (author)

The set-up and calibration of the PIXE-SP System of Elementary Analysis located at the Institute of Physics of the University of Sao Paulo is described. The PIXE-SP, that operates with 8 MeV alpha beam, has been calibrated for elements with Z >= 11, by means of homemade evaporated standard targets of Al, Si, Bacl 2 , K 2 CrO 4 , Ti, Cr, Mn, Fe, Cu, Ge, Ag, Sn, and Au. Those targets are thin, homogeneous, and have been calbrated on a microbalance within an average precision of 6%. The overall precision of the PIXE-SP System is estimated in 10% for elements with 16 2 thick, irradiated with a 10 μC electric charge, shows a minimum of about 0,1 ng (approximated 4 ppm) for Mn. The PIXE-SP System has also been intercalibrated with the PIXE located at University of Gent, Belgium, by means of 12 atmospheric aerosol targets collected on two Batelle Cascade Impactors. The analyzed masses of elements with 16 [pt

In order to confirm the measurement accuracy of PIXE (Particle Induced X-ray Emission), cross-check test were carried out between three laboratories. Thirty single element samples and one plural elements sample were used in the test. The agreements between three laboratories were evaluated to be better than 10% for the most of tested samples. The reproducibility test showed very good agreement and the dispersion in three times repeated PIXE measurements was within 6% on average. Using an automatic time sequence step sampler in Beijing collected atmospheric aerosol samples. Element concentrations were analyzed by PIXE technique. Then the data were analyzed by the absolute principal factor analysis (APFA) to evaluate the principal components and the percent variance explained by them. As a result, it shows that the PIXE analysis combed with statistical method can effectively resolve the aerosol components in urban area and distinguish between local and remote area aerosol components. The atmospheric aerosol samples were collected at four representative sites with an 8-stage cascade impactor sampler and analyzed for their elemental mass concentrations by PIXE analytic method. Based on some indicator elements, the characteristics of size distributions of particles from different sources were obtained

The correct determination of the X-ray peak areas in PIXE spectra by fitting with a computer program depends crucially on accurate parameterization of the detector peak response function. In the Guelph PIXE software package, GUPIXWin, one of the most used PIXE spectra analysis code, the response of a semiconductor detector to monochromatic X-ray radiation is described by a linear combination of several analytical functions: a Gaussian profile for the X-ray line itself, and additional tail contributions (exponential tails and step functions) on the low-energy side of the X-ray line to describe incomplete charge collection effects. The literature on the spectral response of silicon X-ray detectors for PIXE applications is rather scarce, in particular data for Silicon Drift Detectors (SDD) and for a large range of X-ray energies are missing. Using a set of analytical functions, the SDD response functions were satisfactorily reproduced for the X-ray energy range 1-15 keV. The behaviour of the parameters involved in the SDD tailing functions with X-ray energy is described by simple polynomial functions, which permit an easy implementation in PIXE spectra fitting codes.

Information of the chemical properties of rain fallen during the Asian dust (AD) event will help us to better understand the wet scavenging processes of dust particles. In this study, the chemical characteristics of rainwater and individual raindrops fallen during the AD storm have been investigated. The yellowish rainwater and individual raindrops were collected simultaneously in Kyoto, Japan on 7 April 2001. Particle induced X-ray emission (PIXE) was employed in the determination of chemical properties of soluble and insoluble fractions of rainwater. In addition, micro-PIXE was applied to the chemical analysis of residual materials retained in the initial individual raindrops. The pH level of yellowish rainwater was measured around 6.7. In compliance with the general expectation, major components in rainwater were of soil-origin such as Si, K, Ca, Ti and Fe. These soil-related components contributed to as much as 92% of total elemental composition in both soluble and insoluble fractions. By scanning a micro-beam, the residual particle cluster in individual raindrops was reconstructed in terms of an elemental map. This visualized elemental map in fact enabled us not only to estimate the chemical mixing state of raindrop residual particles but also to presume the wet scavenging of dust particles by rainfall

The purpose of this paper was to measure the leaching efficiency for a thermo stated column designed to extract metals in muds originated by foundry process. The results obtained were useful to contemplate different alternatives helping to solve the problem of stocking enormous volumes of polluted sand produced by industries. Samples of residual sands and muds (treated sands) coming from an engine factory and from a thermo stated column respectively, were irradiated using an external beam of 3.55 MeV energy protons. From the quantitative analysis PIXE (Proton Induced X-ray Emission), it was possible to establish the level of pollution in sands due to the foundry processes and to evaluate the leaching efficiency of the output liquid phase from the thermo stated column. For polluted sands, certain cases were observed for which the efficiency was not enough to decrease the level of pollution in, e.g., Cu, Zn, Br and Pb. (Author)

The purpose of this paper was to measure the leaching efficiency for a thermo stated column designed to extract metals in muds originated by foundry processes. The results obtained were useful to contemplate different alternatives helping to solve the problem of stocking enormous volumes of polluted sand produced by industries. Samples of residual sands and muds (treated sands) coming from an engine factory and from a thermo stated column respectively, were irradiated using an external beam of 3.55 MeV energy protons. From the quantitative analysis PIXE (Proton Induced X-ray Emission), it was possible to establish the level of pollution in sands due to the foundry processes and to evaluate the leaching efficiency of the output liquid phase from the thermo stated column. For polluted sands, certain cases were observed for which the efficiency was not enough to decrease the level of pollution in e.g., Cu, Zn, Br y Pb. (Author)

We developed an original preparation method for honey samples (samples in paste-like state) specifically designed for PIXE analysis. The results of PIXE analysis of thin targets prepared by adding a standard containing nine elements to honey samples demonstrated that the preparation method bestowed sufficient accuracy on quantitative values. PIXE analysis of 13 kinds of honey was performed, and eight mineral components (Si, P, S, K, Ca, Mn, Cu and Zn) were detected in all honey samples. The principal mineral components were K and Ca, and the quantitative value for K accounted for the majority of the total value for mineral components. K content in honey varies greatly depending on the plant source. Chestnuts had the highest K content. In fact, it was 2-3 times that of Manuka, which is known as a high quality honey. K content of false-acacia, which is produced in the greatest abundance, was 1/20 that of chestnuts. (author)

Full text: Thaumatococcus danielli (Marantaceae Benn.) Benth [Miraculous berry] is a multi-purpose perennial herb that is widely distributed in the tropical rainforest areas of West Africa. The leaves are simple, broad with slender stems connected underground to the perennial rhizomes. Farmers grow it in pockets within cocoa (Theobroma cacao) and kola (Cola nitida) plantations in South western Nigeria, Ghana and Cameroon. Propagation is mainly by rhizomes cuttings and occasionally by the seed. T. danielli plays very important roles in the rural economy generating income for the peasant farmers and traders. T. danielli is used mainly in three ways by the people. The leaves are used in food wrapping because of its very good flavour and its preservative ability; and roof thatching while the stem is locally used as straw in weaving mats and in making baskets, bags, hats, hand fans and other artistic works. Research has shown that the fruits of T.danielli contain low-calorie protein named 'Thaumatin' which is about 2000 times as sweet as sucrose. The stems also can be processed to produce fibre industrially in addition to the industrial potential of Thaumatin. Thaumatin have been implicated to be suitable sweetener for diabetes patients. However, despite the great economic values, potentials and benefits of T. danielli, there is hardly any data on its elemental compositions. This work therefore presents the elemental composition of T. danielli plant's parts (Ieaves, stems, fruits (mesocarps), seeds and roots (rhizomes)) from six different towns in Osun State of Nigeria using the Particle Induced X-ray Emission (PIXE) technique. The 2.0 MV collimated proton beam from the NEC 1.7 MV 5SDH Tandem accelerator of the Centre for Energy Research and Development(CERD), Obafemi Awolowo University, Ile-lfe, Nigeria was employed for the measurements. The results showed the detection of elements which include K, Ca, Fe, Mn, Sr, Zn, Pb, Br, and CI at various

Full text: Thaumatococcus danielli (Marantaceae Benn.) Benth [Miraculous berry] is a multi-purpose perennial herb that is widely distributed in the tropical rainforest areas of West Africa. The leaves are simple, broad with slender stems connected underground to the perennial rhizomes. Farmers grow it in pockets within cocoa (Theobroma cacao) and kola (Cola nitida) plantations in South western Nigeria, Ghana and Cameroon. Propagation is mainly by rhizomes cuttings and occasionally by the seed. T. danielli plays very important roles in the rural economy generating income for the peasant farmers and traders. T. danielli is used mainly in three ways by the people. The leaves are used in food wrapping because of its very good flavour and its preservative ability; and roof thatching while the stem is locally used as straw in weaving mats and in making baskets, bags, hats, hand fans and other artistic works. Research has shown that the fruits of T.danielli contain low-calorie protein named 'Thaumatin' which is about 2000 times as sweet as sucrose. The stems also can be processed to produce fibre industrially in addition to the industrial potential of Thaumatin. Thaumatin have been implicated to be suitable sweetener for diabetes patients. However, despite the great economic values, potentials and benefits of T. danielli, there is hardly any data on its elemental compositions. This work therefore presents the elemental composition of T. danielli plant's parts (Ieaves, stems, fruits (mesocarps), seeds and roots (rhizomes)) from six different towns in Osun State of Nigeria using the Particle Induced X-ray Emission (PIXE) technique. The 2.0 MV collimated proton beam from the NEC 1.7 MV 5SDH Tandem accelerator of the Centre for Energy Research and Development(CERD), Obafemi Awolowo University, Ile-lfe, Nigeria was employed for the measurements. The results showed the detection of elements which include K, Ca, Fe, Mn, Sr, Zn, Pb, Br, and CI at various

Micro trace elements in the squid statolith, a calcareous stone which acts as a balancer and hearing, was analyzed with Particle Induced X-ray Emission (PIXE) for the Japanese common squid for the first time. Calcium is the main component of the squid statoliths, which means that squid statolith is the pure calcified structure similar to the fish otolith. Beside Ca, Sr was detected with strong dosage, and some other elements as Mn, Fe, Cu, Zn and As were also detected. Possible assumption of intake of microelements to the statoliths and the suitability of PIXE for statoliths analysis are discussed. (author)

This paper reports an example of how the differential PIXE technique can be successfully applied to the investigation of wood or canvas paintings. The work analysed is a famous wood painting by Leonardo da Vinci, the "Madonna dei fusi" (ex-Reford version, 1501), chosen for a pilot study in a wide international project aimed at analysing Leonardo's works of art by means of non-destructive techniques. While illustrating the results obtained concerning the identification of pigments and the discrimination of the stratigraphy of layers, the merits and limits of differential PIXE in general are pointed out.

External beam PIXE analysis allows the non-destructive in situ characterisation of gemstones mounted on jewellery pieces. This technique was used for the determination of the geographical origin of 64 rubies set on a high-valued necklace. The trace element content of these gemstones was measured and compared to that of a set of rubies of known sources. Multivariate statistical processing of the results allowed us to infer the provenance of rubies: one comes from Thailand/Cambodia deposit while the remaining are attributed to Burma. This highlights the complementary capabilities of PIXE and conventional geological observations

External beam PIXE analysis allows the non-destructive in situ characterisation of gemstones mounted on jewellery pieces. This technique was used for the determination of the geographical origin of 64 rubies set on a high-valued necklace. The trace element content of these gemstones was measured and compared to that of a set of rubies of known sources. Multivariate statistical processing of the results allowed us to infer the provenance of rubies: one comes from Thailand/Cambodia deposit while the remaining are attributed to Burma. This highlights the complementary capabilities of PIXE and conventional geological observations.

For biological and environmental samples, PIXE technique is in particular advantage for elemental analysis, but the quantitative analysis implies accomplishing complex calculations that require the knowledge of more than a dozen parameters. Using a genetic algorithm, the authors give here an account of the procedure to obtain the best values for the parameters necessary to fit the efficiency for a X-ray detector. The values for some variables involved in quantitative PIXE analysis, were manipulated in a similar way as the genetic information is treated in a biological process. The authors carried out the algorithm until they reproduce, within the confidence interval, the elemental concentrations corresponding to a reference material

This paper reports an example of how the differential PIXE technique can be successfully applied to the investigation of wood or canvas paintings. The work analysed is a famous wood painting by Leonardo da Vinci, the 'Madonna dei fusi' (ex-Reford version, 1501), chosen for a pilot study in a wide international project aimed at analysing Leonardo's works of art by means of non-destructive techniques. While illustrating the results obtained concerning the identification of pigments and the discrimination of the stratigraphy of layers, the merits and limits of differential PIXE in general are pointed out

The major and minor chemical compositions and trace element content of white glaze made in Qing dynasty at kuan kiln have been determined by PIXE. Experimental results show that trace element contents RbSrZr are useful to distinguish the place of production of ancient porcelain. In the porcelain from different kilns situated in a same province, the trace element contents can be different from each other. Determining and comparing the major and minor compositions and trace elemental concentrations in white glaze by PIXE technique, we can distinguish a precious Qing dynasty porcelain made at kuan kiln from a fake.

Full text: Studies of the role played by elements in fundamental processes in physiology, nutrition, elemental deficiency and toxicity as well as environmental pollution require accurate, quantitative methods with good spatial resolution. the problem of proper measurements of elemental balances and elemental transfers between various levels of biological organisation (from abiotic to biotic systems; along the food chains; within organs and cells) becomes essential for understanding the mechanisms influencing the selection, interaction, distribution and transport of elements. Highly sensitive techniques for bulk elemental analysis are mostly used in these investigations. These techniques usually offer adequate sensitivity, but without spatial resolution. On the other hand, advanced studies of elemental distribution at a cellular level are mostly conducted using techniques with high spatial resolution, but low sensitivity. Ideally, these studies should be conducted on organs and tissues of sizes as far down as the cellular and sub-cellular level. This applies to e.g. future directions in ionomics and metallomics and opens up new, exciting possibilities of studies of trace metal role. The micro-PIXE has been applied in plant sciences for more than thirty years and has reached a high level of maturity. This is one of the few microanalytical, multielemental techniques capable of quantitative studies of elemental distribution at ppm level with with ability to perform quantitative elemental mapping and easy quantification of data extracted from selected micro-areas. Preparation of biological specimens is undoubtedly the crucial and most difficult part of analysis, and only cryotechniques are recommended presently for ali types of microanalytical studies. Established sample preparation protocols will be presented. Most of results are obtained for cryofixed and freeze-dried material but analysis of samples in frozen-hydrated state brings important advantage. Recent

A proton-induced x-ray emission analysis (PIXE) system using 2-MeV protons was developed. Measurements are being made in connection with several research projects. A study is being conducted to provide ecological baseline information in the region of the Navajo and the proposed Kaiparowits coal-fired electric generating stations. Trace-element measurements in this study are reported on air-particulate samples, small rodent tissues, soils, and plants. In another study air particulates collected near a source of SO 2 are extracted from the collection filter with an HCl solution and sulfate and sulfite ions are determined by calorimetric methods. The extraction solution is also analyzed by PIXE to determine the elemental composition. The latter information is necessary for an understanding of possible interferences with the calorimetric method and also indicates the heavy metals emitted by the source. Studies on human autopsy tissues, archeological artifacts, and in regular graduate and undergraduate laboratory classes are mentioned briefly

As part of studies into the mineralogical distribution of gold in volcanogenic massive sulfide (VMS) ore deposits PIXE analysis by the proton microprobe has been used to determine the gold content of pyrite and arsenopyrite from the Rosebery, Mt. Chalmers and Mt. Lyell deposits. In addition, the concentrations of Co, Ni, Cu, Zn, As, Sr, Y, Zr, Mo, Ag, Sb, Te, Au, Tl, Pb and Bi were also determined. 4 refs., 1 tab

X-rays may be produced following the excitation of target atoms induced by an energetic incident ion beam of protons. Proton induced X-ray emission (PIXE) analysis has been used for many years for the determination of elemental composition of materials using X-rays. Recent interest in the proton induced X-ray emission cross section has arisen due to their importance in the rapidly expanding field of PIXE analysis. One of the steps in the analysis is to fit the measured X-ray spectrum with theoretical spectrum. The theoretical cross section and yields are essential for the evaluation of spectrum. We have theoretically evaluated the PIXE cross sections for trace elements in the lung and breast cancer tissues such as Cl, K, Ca,Ti, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Br, Rb, P, S, Sr, Hg and Pb. The estimated cross section is used in the evaluation of Proton induced X-ray emission spectrum for the given trace elements.We have also evaluated the Proton induced X-ray emission yields in the thin and thick target of the given trace elements. The evaluated Proton induced X-ray emission cross-section, spectrum and yields are graphically represented. Some of these values are also tabulated. Proton induced X-ray emission cross sections and a yield for the given trace elements varies with the energy. PIXE yield depends on a real density and does not on thickness of the target. (author)

The analyses of source materials combined with analyses of archaeological objects could distinguish from pieces produced in different regions and periods. For coins, chemical differences that occur during preparation of alloys will affect the elemental composition and could be used for the identification of technologies and workshops and also to distinguish between originals and counterfeits. We illustrate with the case of Greek Apollonia and Dyrrhachium silver drachmas emitted by these old cities for Pompejus during the First Roman Civil War between Julius Caesar and Pompejus, coins found on the actual territory of Romania (ancient Dacia), probably used as bursaries to pay the Dacian mercenaries allied with Pompejus. To analyze the chemical composition of these coins, we used two methods: Am-241 gamma source based X-Ray Fluorescence (XRF) and in vacuum 3 MeV protons Particle Induced X-ray Emission (PIXE). XRF measurements were done with a spectrometer consisting of a 30 mCi Am-241 annular source, a vertical Si(Li) detector and a conventional electronic chain. For PIXE, we used 3 MeV protons (15-20 nA intensity on the sample using a pile-up rejector system) accelerated at Bucharest 8 MV High Voltage Tandem, a horizontal HPGE detector placed perpendicularly on the beam direction and a conventional electronic chain. Some special measurements on the edge of some coins (to identify plated exemplaires) were done using the ATOMKI Debrecen Van de Graaf 2 MeV protons microprobe, in the frame of European Action COST G1. We analysed approx. 300 drachmas. Five main categories were found: - original coins (similar to drachms emitted before the Civil War) with 97-99 percent silver, low (1-2 percent) copper content, -debased coins with silver content down to 70 percent and copper content from 5 to 25 percent, probably emitted due to inflation problem, normal phenomenon for an economy in war, -official (original dies) counterfeits from bronze (70 percent copper and 30 percent tin

An interactive computer program for the analysis of Pixe spectra is described. The fitting procedure consists of computing a function which approximates the experimental data. A nonlinear least-squares fitting is used to determine the parameters of the fit. The program takes into account the low energy tail and the escape peaks

The AstroPix project provides one-stop-shopping for an extensive collection of the finest astronomical imagery, sourced from some of the world’s most prominent observatories. The archive is made possible by a grassroots effort to tag publicly-released imagery using the Astronomical Visualization Metadata (AVM) standard, which captures rich contextual information for each image. While the site has been in development for many years, it is now supported under NASA’s Universe of Learning collaboration, and AstroPix has been updated and deployed to cloud services. The AVM tags provide many unique features including spectral color assignments, sky context (using AAS WorldWide Telescope APIs), and direct links to the original source material on the web. The 7,000+ assets currently include imagery provided by Chandra, ESO, GALEX, Herschel, Hubble, NuSTAR, Spitzer, and WISE. The assets are also provided for use in the planetarium community by supporting the Data2Dome (D2D) initiative. AstroPix imagery is designed to be used in a variety of unique ways that benefit formal and informal education as well as astronomers and the general public. Observatories can add their own image archives to AstroPix by tagging their assets and providing a simple XML feed, increasing the value of their data to the community at large.

A scattering chamber for Particle Induced x-ray Emission (PIXE) analysis is described. This chamber was designed and constructed for thin film thickness measurements and depth profiling. The chamber operation characteristics and versatility in materials analysis are shown. (Author). 18 refs, 6 figs

Limits of detection (LODs) for aerosol samples collected using PIXE International cascade impactors, were improved approximately 50% after reducing the cross-sectional area of the analytical beam based on results obtained from microscope photographs of aerosol deposits. Improvements in LODs were most noticeable for selected elements collected on the smaller stages of the impactor (stages 1-3)

In the 1980s and 1990s nearly half of the elemental analyses of atmospheric aerosol samples were performed by PIXE. Since then, other techniques for elemental analysis became available and there has been a steady increase in studies on organic aerosol constituents and other aspects of aerosols, especially in the areas of nucleation (new particle formation), optical properties, and the role of aerosol particles in cloud formation and properties. First, a brief overview and discussion is given of the developments and trends in atmospheric aerosol analysis and research of the past three decades. Subsequently, it is indicated that there is still invaluable work to be done by PIXE in atmospheric aerosol research, especially if one teams up with other aerosol researchers and performs complementary measurements, e.g., on small aerosol samples that are taken with high-time resolution. Fine examples of such research are the work done by the Lund group in the CARIBIC aircraft studies and the analysis of circular streaker samples by the Florence PIXE group. These and other examples are presented and other possibilities of PIXE are indicated.

GridPix detectors are a new kind of detectors combining a high density pixelized readout ASIC with a Micromegas gas amplification stage. Because of the alignment of mesh holes and pixels, a high efficiency for detecting and separating single primary electrons is reached. This feature leads to excellent spatial and energy resolutions as demonstrated by several different setups.

The quantitative analysis of steel endodontics tools was carried out using low-energy protons (≤ 700 keV). A computer program for a thick-target analysis which includes enhancement due to secondary fluorescence was used. In this experiment the L-lines of indium are enhanced due to the proximity of other elements' K-lines to the indium absorption edge. The results show that the ionization cross section expression employed to evaluate this magnitude is important. (orig.)

The quantitative analysis of steel endodontics tools was carried out using low-energy protons (/le/ 700 keV). A computer program for a thick-target analysis which includes enhancement due to secondary fluorescence was used. In this experiment the L-lines of indium are enhanced due to the proximity of other elements' K-lines to the indium absorption edge. The results show that the ionization cross section expression employed to evaluate this magnitude is important. (orig.).

The possibility of non-destructive elemental analysis makes PIXE a very attractive technique in archaeological provenance studies. This technique has been fruitfully implemented on two different facilities to address the issue of obsidian provenance in the Mediterranean and in surrounding regions. At C2RMF, we took advantage of the possibility to analyze large archaeological pieces with the external micro-beam set-up. At CENBG, we used the nuclear microprobe providing a 5 μm beam diameter in large scans (700 x 700 μm 2 ) to control the homogeneity of elemental distribution. In both cases we dosed the same set of 13 elements: Na, Al, Si, K, Ca, Ti, Mn, Fe, Zn, Ga, Rb, Sr and Zr. While at C2RMF, two Si(Li) detectors were used simultaneously to measure all elements at once with 3 MeV protons, at CENBG where only one detector was available, the light elements Na to Fe were determined with a 1.5 MeV beam, and the heavy ones, including Fe, with a beam energy of 2.7 MeV. In Western Mediterranean, it is possible with PIXE to differentiate all obsidian sources of archaeological significance. Examples are given of obsidian provenances from Neolithic sites of France and from the islands of Corsica and Sardinia. In the Near East, we can differentiate the Cappadocian and Eastern Anatolian obsidian sources used during the early Neolithic. This is illustrated by examples taken from Neolithic sites of the Middle Euphrates Valley (Syria)

Full text: A recent EU regulation (EN 149022005) requests the quantification of selected metals in the atmospheric particulate by mineralization with H{sub 2}0{sub 2} and HN0{sub 3} in microwave oven.This method might possibly conflict with the determination of the total metal content. In fact, the more the aerosol is enriched in crustal elements the more the difference in the two methods are expected, since the H{sub 2}0{sub 2}+ HN0{sub 3}, extraction is not reliable for metals in silicate form. In order to evaluate the extracted fraction, PIXE and ICP-AES measurements were carried out on the two halves of a series of PM10 and PM2.5 samples collected on Teflon filters in an urban site in the surrounding of Florence (Italy). An ICP-AES (Inductively Coupled Plasma -Atomic Emission Spectroscopy) method was optimized by an ultrasound nebuliser (CETAC 5000 AT+), in order to improve reproducibility and detection limit. In these conditions, it was possible quantifying AI, As, Cr, Cu, Fe, Mn, Ni, Pb and Vatsub-ppb levels. PIXE analysis using the external beam set-up at LABEC and a 3 MeV proton beam was carried out in order to measure the total elemental content of the metals. By comparing the ICP-AES and the PIXE results, a preliminary evaluation of the efficiency of the H{sub 2}0{sub 2} and HN0{sub 3} extraction method was performed. The obtained results (the mean values for the ICP-AES/PIXE ratio are reported in Table 1) show that the extraction procedure following the EN 14902 directive allows quantitative recoveries (80-120%, including the analytical uncertainties)for the majority of the analysed metals, especially for those mainly emitted by anthropic sources. This result points out that anthropic metals are present in the atmosphere as relatively available species (free metals, labile complexes, carbonates, oxides). On the contrary, lower recoveries were obtained for AI (mean value around 75%), a metal that has a relevant crustal fraction. Percentage of recovery of

The objective of this research is to determine whether there is a difference in the Ca, P, Fe, F, Mg, and Sr concentrations in teeth from children with and without cystic fibrosis (CF) as a function of age, sex of the child, maternal smoking habit, maternal drinking habit, and fluoridation of water supply. The nuclear analytical methods used were Proton-Induced X-Ray Emission (PIXE) and Proton-Induced Gamma Emission (PIGE). The findings are: (1) the concentration of Mg is higher in the teeth of children with cystic fibrosis who took antibiotics other than tetracycline (CF+NT) than in non-cystic fibrosis (NCF) teeth for the 'female' category; (2) P concentration is less in (CF+NT) teeth for the 'age greater than ten' group; (3) Fe concentration is greater for females in the NCF group; (4) Ca and Fe concentrations are lower for CF than for NCF in the 'mother smokes' group; (5) F and Sr concentrations for CF+NT are higher for the 'mother drinks' group than for the 'mother does not drink' group; (6) 'mother smokes' shows a depletion of Ca and Fe compared to 'mother does not smoke' for CF+NT. (7) 'fluoridation of water supply' shows an increase in F, except for NCF teeth. (author)

Full text: The non-destructive study of artistic and archaeological objects relies on the use of a large panel of modern analytical tools. Among them, PIXE plays a prominent role due to its almost unique combination of excellent analytical features in terms of sensitivity and accuracy combined with a non-destructive and even non-invasive character. the latter advantage stems from extensive instrumental progress - like the external beam - carried out since the advent of PIXE in the 1970s to account for the precious and unique nature of artworks and archaeological artifacts that preclude any sampling or damage. the situation has however evolved in the recent years as several competing techniques providing non-destructively the chemical composition have arisen, which more or less shake the privileged status of PIXE. On one hand, analytical techniques implemented with tabletop or movable XRF instruments have been massively developed, which allow in situ analysis and represent a progress in terms of artworks safety and flexibility of analysis. On the other hand, access to synchrotron radiation facilities is becoming easier and therefore the use of the powerful X-ray absorption techniques (XANES, EXAFS), that add chemical environment information to the elemental analysis, is progressively gaining popularity. Considering these trends, it seems important to reassess the place of PIXE in the field of art and archaeology and to underline its specific assets. the aim of this article is to pinpoint the situation where PIXE is the best analytical tool with regard to the specificity of art and archaeological items and to stress the new challenges it will have to face. Case studies carried out with the AGLAE facility of the C2RMF will illustrate the situations where PIXE exhibits specific advantages: Light element measurement. The high ionization cross section of light elements by charged particles favors the accurate measurement of sodium, magnesium, aluminum and silicon, whose

Full text: The non-destructive study of artistic and archaeological objects relies on the use of a large panel of modern analytical tools. Among them, PIXE plays a prominent role due to its almost unique combination of excellent analytical features in terms of sensitivity and accuracy combined with a non-destructive and even non-invasive character. the latter advantage stems from extensive instrumental progress - like the external beam - carried out since the advent of PIXE in the 1970s to account for the precious and unique nature of artworks and archaeological artifacts that preclude any sampling or damage. the situation has however evolved in the recent years as several competing techniques providing non-destructively the chemical composition have arisen, which more or less shake the privileged status of PIXE. On one hand, analytical techniques implemented with tabletop or movable XRF instruments have been massively developed, which allow in situ analysis and represent a progress in terms of artworks safety and flexibility of analysis. On the other hand, access to synchrotron radiation facilities is becoming easier and therefore the use of the powerful X-ray absorption techniques (XANES, EXAFS), that add chemical environment information to the elemental analysis, is progressively gaining popularity. Considering these trends, it seems important to reassess the place of PIXE in the field of art and archaeology and to underline its specific assets. the aim of this article is to pinpoint the situation where PIXE is the best analytical tool with regard to the specificity of art and archaeological items and to stress the new challenges it will have to face. Case studies carried out with the AGLAE facility of the C2RMF will illustrate the situations where PIXE exhibits specific advantages: Light element measurement. The high ionization cross section of light elements by charged particles favors the accurate measurement of sodium, magnesium, aluminum and silicon, whose

This experimental study consists in make falling a particle beam on a collected sample of the air pollutants. In the present work protons coming from a particle accelerator were used. The magnet baffle of this it selects the protons energy according to the experiment. The beam current is generally of the order of nano amperes and it can be measured and integrated. At the interact the beam with the sample there are produced X rays characteristic of each one of those present elements in it. These X rays are registered by a Li-Si detector of which proportional pulses are obtained to the energy of the same ones. Finally this pulses are electronically processed in a typical arrangement (preamplifier-amplifier-multichannel) that delivers an energy spectra characteristic of the sample elements. Each one of the peaks of the spectra represents an element which is possible to identify. From the under curve area of each peak it can be evaluated the concentration corresponding to each element. (Author)

Proton-induced X-ray emission (PIXE) and light element analysis have been performed with the nuclear microprobe at the Laboratoire Pierre Suee (Saclay-France) in glass inclusions of the carbonaceous chondrites: Allende, Kaba and Renazzo, and in the achondrite meteorite: Chassigny. Carbon contents in olivine of chondrules are below the nuclear reactions analysis (NRA) detection limit, however, glasses from glass inclusions hosted by these grains, contain an appreciable and highly variable quantities of carbon (200-1600 ppm). This could indicate variable amounts of C trapped during glass inclusion formation. On the other hand, nitrogen is present in highly variable amounts in glasses of both, chondrites and achondrites minerals. Its abundance, correlated with depth from the section surface which suggests loss of N during analyses and therefore the possible existence of a very mobile (volatile?) species. A chondritic Rb/Sr and K/Rb ratio obtained by PIXE analyses in the glass-bearing inclusions of the Chassigny meteorite points towards a primitive source for the glass precursor of Chassigny inclusions

An investigation was conducted on the status of trace and minor elements in some foodstuffs, meats and also drinking water in Bangladesh, using proton induced X-ray emission (PIXE), radioisotope-induced X-ray fluorescence (XRF), atomic absorption spectrophotometry (AAS) and also ion-selective electrode techniques. The elemental concentrations of K, Ca, Mn, Fe, Ni, Cu, Zn, As, Br, Rb and Sr, were determined in the samples by comparison with X-ray yield curves constructed from IAEA and NBS standard reference materials. Cadmium and zinc in the drinking water of Bangladesh was determined by AAS followed by solvent extraction technique. The total iodine content in different types of vegetables was determined by alkali ashing followed by the ion-selective electrode technique. The results indicate that none of the food regimes and also drinking water investigated here is burdened with heavy metals beyond permissible limits. The significance of the results is discussed in relation to human health an diseases. Three IAEA (2-1, and 2-2 and 2-3) secondary reference standard samples were also analyzed for intercomparison studied using PIXE and ASV techniques. (author). 4 refs, 7 tabs

Localization of Hg in root tissues of vetivergrass (Chrysopogon zizanioides) was investigated by micro-Proton Induced X-ray Emission (PIXE) spectrometry to gain a better understanding of Hg uptake and its translocation to the aerial plant parts. Tillers of C. zizanioides were grown in a hydroponic culture for 3 weeks under controlled conditions and then exposed to Hg for 10 days with or without the addition of the chelators (NH(4))(2)S(2)O(3) or KI. These treatments were used to study the effects of these chelators on localization of Hg in the root tissues to allow better understanding of Hg uptake during its assisted-phytoextraction. Qualitative elemental micro-PIXE analysis revealed that Hg was mainly localized in the root epidermis and exodermis, tissues containing suberin in all Hg treatments. Hg at trace levels was localized in the vascular bundle when plants were treated with a mercury solution only. However, higher Hg concentrations were found when the solution also contained (NH(4))(2)S(2)O(3) or KI. This finding is consistent with the observed increase in Hg translocation to the aerial parts of the plants in the case of chemically induced Hg phytoextraction.

Time-resolved deposits of welding shop air particulates have been obtained using a streak sampling system. PIXE analysis of these deposits, using 2 MeV protons, typically revealed the presence of a large number of elements, with many in the range Z = 11-30. Strong variations, up to three orders of magnitude, in the concentrations of several elements such as Al, Si and Fe as well as Zn, Na, K and Ca were found. The 2 h sampling resolution normally used was found to be insufficient to follow the short pollution episodes that regularly occur in a welding shop environment and so sampling with a 20 min resolution was used. The variation of elemental concentrations for different sampling times together with information on the physical nature of these air particulates, determined with a scanning electron microscope (SEM) and Si(Li) X-ray detector attachment, are presented. This type of information together with that obtained from the PIXE analysis is of importance industrial hygiene studies. The need to make corrections for partial filter clogging, based on air-flow rate monitoring, is discussed. (orig.)

The concentration of elements with Z > 18 is measured in tree rings from forests at the surroundings of the Mexico Valley: El Chico National Park (ECP) and Desierto de los Leones National Park (DLP). The analysis was done by simultaneous PIXE-RBS using an external proton beam on tree rings of Pine and Sacred fir (species Pinus montezumae and Abies religiosa, respectively). This study provides information about the elemental concentration in trees of those parks during the years from 1965 to 2003. Typical elements such as K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Br, Sr and Pb were detected using PIXE technique while the wood matrix composition (mainly C and O) was determined by RBS. In general, elemental contents present large variations but concentrations oscillate around the mean value during this period of time. Nevertheless, the measurements showed some trends for Fe and Zn in the tree-rings elemental composition that may be correlated to recent volcanic activities in the region. The low Mn contents indicate soil acidification in DLP from 1968 and the forest decline in ECP during the last 15 years

Our work on heavy metals in the estuarine environment has involved the use of two multielement techniques: neutron activation analysis (NAA) and proton-induced X-ray emission (PIXE) analysis. As PIXE is essentially a surface analytical technique problems may arise due to sample inhomogeneity and surface roughness. In order to assess the contribution of these effects we have compared the results from PIXE analysis with those from a technique which analyzes a larger bulk sample rather than just the surface. An obvious method was NAA. A series of sediment samples containing particles of variable diameter were compared. Pellets containing a few mg of sediment were prepared from each sample and analyzed by the PIXE technique using both an absolute and a comparitive method. For INAA the rest of the sample was then irradiated with thermal neutrons and element concentrations determined from analyses of the subsequent gamma-ray spectrum. Results from the two methods are discussed.

The proton-induced X-ray emission (PIXE) technique was applied to the identification and analysis of gunshot residues. Studies were made of the type of bullet and bullet hole identification, firearm discharge element profiles, the effect of various target backings, and hand swabbings. The discussion of the results reviews the sensitivity of the PIXE technique, its nondestructive nature, and its role in determining the distance from the gun to the victim and identifying the type of bullet used and whether a wound was made by a bullet or not. The high sensitivity of the PIXE technique, which is able to analyze samples as small as 0.1 to 1 ng, and its usefulness for detecting a variety of elements should make it particularly useful in firearms residue investigations

A combined PIXE and XPS analysis has been performed on a few Roman coins of the republican and imperial age. The purpose was to investigate via XPS the nature and extent of patina in order to be capable of extracting PIXE data relative to the coins bulk. The inclusion of elements from the surface layer, altered by oxidation and inclusion, is a known source of uncertainty in PIXE analyses of coins, performed to assess the composition and the provenance

In the present study, possible differences in the mineral composition of transgenic versus non-transgenic sorghum grains were investigated using inductively coupled atomic emission spectroscopy (ICP-AES); and, in-tissue elemental mapping by micro Proton-Induced X-ray Emission (micro-PIXE) analysis. ICP AES was used to analyse the bulk mineral content of the wholegrain flour derived from each genotype; whilst micro-PIXE was used to interrogate localised differences in mineral composition specific to certain areas of the grain, such as the bran layer and the central endosperm tissue. According to the results obtained, no significant difference in the average Fe, Zn or Ca content was found to differentiate the transgenic from the wild-type grain using ICP-AES. However, using micro-PIXE, a significant reduction in zinc could be detected in the bran layer of the transgenic grains relative to wild-type. Although it is difficult to draw firm conclusions, as a result of the small sample size used in this study, micro-PIXE has nonetheless proven itself as a useful technique for highlighting the possibility that there may be reduced levels of zinc accumulation in the bran layer of the transgenic grains. Given that the genetic modification targets proteins that are highly concentrated in certain parts of the bran tissue, it seems plausible that the reduced levels of zinc may be an unintended consequence of the silencing of kafirin proteins. Although no immediate health or nutritional concerns emerge from this preliminary finding, it is noted that zinc plays an important biological role within this part of the grain as a structural stabiliser and antioxidant factor. Further study is therefore needed to assess more definitively the extent of the apparent localised reduction in zinc in the transgenic grains and how this may affect other important grain quality characteristics.

The fine white porcelains of Xing Kiln, Ding Kiln and Jingxing Kiln are very similar or alike in many aspects, such as typology of the vessel, texture of the body, colors of the body and the glaze. It is difficult for the archaeologists to distinguish the provenance using traditional methods. Nuclear analytical techniques (INAA, PIXE, XRF, SRXRF) have been widely employed for the provenance study of cultural relics in recent years due to their unique advantage, i.e. capable of nondestructive analysis. The element contents in the body and glaze of white porcelain shards with known provenance were determined by INAA and PIXE. In the meanwhile blind samples were prepared and analyzed in the same way. The differences of the element abundance patterns were processed by multivariate statistical analysis. On the basis of the analytical data and the statistical results, the discriminating criteria for provenance identification are obtained and verified by the blind samples.

Micro-PIXE analysis of trace elements in otoliths has been used as the basis for several projects on char, a fish that is important for aboriginal subsistence fisheries in Arctic Canada. Life-history patterns were originally inferred from micro-PIXE line scans of Sr distribution. These were confirmed by superposition of Sr distribution patterns on optical images of otoliths of tag-recaptured fish. Char from various populations showed differentiation in otolith primordial Sr concentration; this enables us to differentiate biological stocks and, it is hoped, eventually to assign individuals from mixed-stock fisheries to their stock of origin. Zn oscillations also correlate with annular structure and provide additional temporally constrained information on fish habitat and behaviour

External-beam PIXE was used to determine the major, minor and trace elements of 45 nephrite minerals from 14 different deposits, including China and other countries. Depending on the R∗ value (mole percent of Mg 2+/(Mg 2+ + Fe 2+(3+))) and content of Cr, Co and Ni, two types of nephrite minerals from dolomite and serpentinized ultramafic deposits can be more accurately distinguished. Besides, the nephrite minerals from Xiaomeiling and Wenchuan deposit can be distinguished with others from dolomite deposits, through the content of Sr and Mn/Fe value, respectively. Moreover, depending on the Sr content, clear evidence was given to prove that the raw materials of ancient nephrite artifacts from Liangzhu culture ruins are not from Xiaomeiling nephrite deposit. Furthermore, PIXE as a non-destructive method will be more used to study ancient nephrite artifacts, so these results can provide scientific basis for seeking the provenance of nephrite raw materials.

Aerosol samples from the western North Pacific Ocean are collected during a cruise of R/V Hakuhomaru from Japan to Hawaii and they are analyzed by PIXE (particle induced X-ray emission). Concentrations of radon daughters are measured with CR-39 track detectors mounted on the impactor to estimate the transport time of air mass from the Asian Continent. Distributions of particulate element concentrations clearly demonstrate the influence of the westerlies. Strong correlations are observed between fine sulphur concentrations and those of heavy metals such as Fe and Zn. Vertical profiles of heavy metal elements contained in marine particulates are also investigated at a trench in the Pacific Ocean and basins in the Japan Sea. Particulate element concentrations determined by PIXE agree well with those determined by chemical analysis of filtered/total water. Remarkable changes in depth profiles of particulate manganese are observed at the trench, which suggest horizontal transport of marine particulates from the trench wall. (N.K.)

Two WC–Co powders have been analyzed using micro-PIXE to identify elemental concentration and distribution. A powder recycled primarily from used mining components and a powder produced exclusively from fresh raw materials was studied. Elemental mapping of major elements as well as impurities, within powder granule cross sections, was performed. Contaminants (e.g. Fe and Ni) from manufacturing processes, as well as trace impurities (e.g. Cr, Cl, Ca and S) from recycling were detected, quantified and compared. The extent of increased concentrations of impurities resulting from recycling were observed, demonstrating the potential for PIXE as a characterization tool for detecting trace elements in cemented carbides, allowing for future improvements in the manufacturing and recycling processes

The variation of elemental concentrations in exhaust gas of a Diesel engine with the outputs was studied. Particulates in high temperature gas were collected on silica fiber filters and analyzed by PIXE method. Concentrations of S and V were nearly proportional to particulate masses and fuel consumption rates per discharging rates of exhaust gas respectively. While, concentrations of Fe and Mn were markedly increased together with engine outputs, and Mn/Fe ratios were nearly equal to those of the material of piston rings and the cylinder liner. Concentrations of the elements contained in lubricant, such as Ca and Mo, were also conspicuously increased with the outputs. It was shown that PIXE analysis is a useful tool for engine diagonostics owing to its high sensitive multi-elemental availability without chemical treatments. (author)

Pteris vittata is a fern reported to be an arsenic hyper-accumulator. To develop the practical application of the fern to a phytoremediation technique, it is necessary to explicate the effective accumulation mechanism. In this study, the arsenic distribution and the elemental correlation in the cellular level were examined in the fronds supplied with arsenate and arsenite separately via xylem vessel using an in-air micro-PIXE system at Tohoku University. The difference in transportation rate between arsenate and arsenite as well as the translocation of elements necessary for plant metabolism was revealed in different tissues of the fronds accumulating arsenic in high concentration. Hence, the in-air micro-PIXE analysis is an effective measure for undertaking phytoremediation research of hyper-accumulator plants. (author)

A new sample chamber for micro-PIXE analysis of geological thick samples has been successfully developed. A target in the sample chamber is normal to the beam and Si(Li) detectors are located at 135deg to the beam direction. For the sample observation, a normal viewing optics with the optical axis collinear with the beam is achieved by a combination of long working distance microscope and mirror with a central hole for the beam transmission. The normal incidence beam and normal viewing are essential to raise a spatial resolution of the thick target analysis. In addition, the sample chamber has fulfilled ten requirements as for material, driving stage, X-ray absorbers, space for another detector, etc. The information obtained by the development can give a new guide to manufacture the sample chamber for the micro-PIXE. (author)

We have developed a small wavelength dispersive X-ray spectrometer to explore the possibility of performing chemical speciation on microscopic samples utilizing focused ion beams available at the Rudjer Boskovic Institute ion microprobe. Although PIXE spectra are in principle chemically invariant, small influence of chemical effects could be observed even with Si(Li) or SDD detectors. Such chemical effects can be clearly seen with high resolution crystal X-ray spectrometers having energy resolution of several eV. A dedicated vacuum chamber, housing the diffraction crystal, sample holder and CCD X-ray detector, was constructed and positioned behind the main ion microprobe vacuum chamber. Here we will briefly describe the spectrometer, and illustrate its capabilities on measured K X-ray spectra of selected sulfur compounds. We will also demonstrate its abilities to resolve K and M X-ray lines irresolvable by solid state ED detectors usually used in PIXE.

The applicability of PIXE for multielemental analysis is demonstrated. The method is used in a major systematic study on hair samples using one target analysis. The pathological state considered is agitated elderly people. The main elements examined are S, K, Ca, Fe, Co, Ni, Cu, Zn, Se, Br, Hg and Pb. The minimum detectable limits are 1-10 ppm using 180 μg of dry hair at 25 μe irradiations for elements between K and Br. The significance of differences between the hair elements in control populations and patients suffering from the pathological conditions are investigated. Investigations of possible linear and multiple-correlations between elements in each population are made. The work indicates that some elements do exhibit variation with pathological state, and the multielement PIXE analysis gives useful information about the subject. (author). 13 refs, 4 figs, 6 tabs

Two WC–Co powders have been analyzed using micro-PIXE to identify elemental concentration and distribution. A powder recycled primarily from used mining components and a powder produced exclusively from fresh raw materials was studied. Elemental mapping of major elements as well as impurities, within powder granule cross sections, was performed. Contaminants (e.g. Fe and Ni) from manufacturing processes, as well as trace impurities (e.g. Cr, Cl, Ca and S) from recycling were detected, quantified and compared. The extent of increased concentrations of impurities resulting from recycling were observed, demonstrating the potential for PIXE as a characterization tool for detecting trace elements in cemented carbides, allowing for future improvements in the manufacturing and recycling processes.

The alleged use of potassium bromate (KBrO3) in bread baking led a few authors to report on the chemical methods for the determination of KBrO3 levels in bread. In order to examine the potentials of a non chemical particle induced X-ray emission (PIXE) method for this purpose, six sets of samples, each composed of flour, dough and bread from a production batch were analysed. The samples were obtained from six different bakers of bread at Ile-Ife, Nigeria. The flour samples were air-dried while others were freeze dried at about -16 °C. The samples were homogenised in an agate mortar and then pelletised. Samples were analysed at the CTN standard PIXE setup and standard procedures for thick target samples analysis were followed. In some samples significant concentrations of bromine were found. In the present work we present possible explanations for the presence of this potentially dangerous contaminant in the samples.

Atmospheric aerosol and hydrometeor particles act decisively on our weather, climate and thereby on all living conditions on Earth. Particle induced X-ray emission (PIXE) analysis has been demonstrated to be an extremely valuable tool for quantitative and qualitative elemental analysis of aerosol particles and hydrometeors. Reliability and detection limits of PIXE are determined, including comparison with other techniques. Aerosol particles are collected on a global scale in ground stations, or by ships and by planes. Correlation between wind direction and elemental composition of atmospheric aerosols, elemental particle size distributions of the tropospheric aerosol, aerosol elemental composition in particle size fractions in the case of long range transport, transport pathways of pollution aerosol, and trace element content precipitation are discussed. Hydrometeors were studied in the form of rain, snow, fog, dew and frost. The time dependence of the melting process of snow was studied in detail, in particular the washout phenomena of impurity ions. (orig.)

This paper reports some new results obtained by PIXE on Chinese ancient porcelain. The first results concern the provenance of blue and white porcelain made during the Tang Dynasty (AD618-907), which are the earliest products found in China. The PIXE experimental results show that they were fired in Huangye Kiln, Gongyi, Henan Province. The chemical composition of the body, white glaze and of the cobalt pigment will be reported. This paper also reports the results for early Chinese blue and white porcelain made under the Yuan dynasty (AD1206-1368) in Jingdezhen, Jiangxi Province. Experimental results show that the chemical composition of the cobalt pigment used by officers and popular are similar. These materials were imported from another country. The local asbolite was used as cobalt pigment material since the early Ming Dynasty (AD1368-1644) in Jingdezhen at folk kiln, and it was used at official kiln until the 16th century.

This paper reports some new results obtained by PIXE on Chinese ancient porcelain. The first results concern the provenance of blue and white porcelain made during the Tang Dynasty (AD618-907), which are the earliest products found in China. The PIXE experimental results show that they were fired in Huangye Kiln, Gongyi, Henan Province. The chemical composition of the body, white glaze and of the cobalt pigment will be reported. This paper also reports the results for early Chinese blue and white porcelain made under the Yuan dynasty (AD1206-1368) in Jingdezhen, Jiangxi Province. Experimental results show that the chemical composition of the cobalt pigment used by officers and popular are similar. These materials were imported from another country. The local asbolite was used as cobalt pigment material since the early Ming Dynasty (AD1368-1644) in Jingdezhen at folk kiln, and it was used at official kiln until the 16th century.

In the present work the moss biomonitoring technique and the combination of two analytical techniques - Particle Induced X-ray Emission (PIXE) and Inductively Coupled Plasma (ICP) - were applied for assessing environmental situation from the point of view of air polluting along the transect from north to south of the Dambovita County. PIXE analysis at the Tandem Accelerator FN-8 of the National Institute of Nuclear Physics - Horia Hulubei of Magurele, Bucharest, allowed determination of P, S, Cl, K, Ca, Mn, Fe, Ni, Cu, Zn, As, Sr, Cd and Pb in samples. ICP analyses were made using a Baird ICP2070 - Sequential Plasma Spectrometer in Targoviste and we determined in samples the concentration of Li, B, Na, and Mg together with Cd and Pb. The obtained results will permit to determine the regional extent of heavy metals and toxic elements atmospheric pollution and to identify specially affected areas and local sources of

This paper reports some new results obtained by PIXE on Chinese ancient porcelain. The first results concern the provenance of blue and white porcelain made during the Tang Dynasty (AD618-907), which are the earliest products found in China. The PIXE experimental results show that they were fired in Huangye Kiln, Gongyi, Henan Province. The chemical composition of the body, white glaze and of the cobalt pigment will be reported. This paper also reports the results for early Chinese blue and white porcelain made under the Yuan dynasty (AD1206-1368) in Jingdezhen, Jiangxi Province. Experimental results show that the chemical composition of the cobalt pigment used by officers and popular are similar. These materials were imported from another country. The local asbolite was used as cobalt pigment material since the early Ming Dynasty (AD1368-1644) in Jingdezhen at folk kiln, and it was used at official kiln until the 16th century

Several techniques have been utilized in studying atmospheric contamination samples. However, each lack some characteristics required for these studies. Spectroscopy of X-rays particularly where excitation models are produced using charged particles (Particle Induced X-ray Emission, PIXE), for its high sensitivity, is the one that best fitting itself to the scheme of analysis required. In this paper we report some qualitative results of the atmospheric aerosol samples collected in Mexico City. (Author)

The chemical compositions of 42 obsidian pre-Hispanic artifacts from Tancama and Purisima, both archaeological sites of La Sierra Gorda Valleys, Mexico, were analyzed by PIXE technique. These obsidians came from four sources: Sierra de Pachuca Hidalgo, Paraiso Queretaro, Ucareo Michoacan and mainly from Zacualtipan/Metzquititlan Hidalgo. According to archaeological evidences, La Sierra Gorda valleys participated in commercial exchange with other regional sites, from Classic to Post-classic periods (A.D. 300-1500).

STIM (scanning transmission ion microscopy) tomography has been shown to be a valuable method for the three-dimensional characterization of microsamples. It has, however, rarely been employed for the study of single cells, since a free-standing sample is needed for an ordinary tomography experiment. This requirement places high demands on sample preparation techniques. In this study cells fixated on a substrate rather than free-standing were used for tomography. Since the substrate prevented a full rotation of the sample an algorithm for limited-angle tomography was devised. STIM projections covering only a limited angular range of ca. 120 o were supplemented with simulated projections generated from a back and forth iteration between real space and Radon space. The energy loss caused by the substrate was subtracted from each projection. The cells were reconstructed using filtered backprojection. The surface of the cells as well as some interior structures could be reconstructed. Following the STIM projections a lesser number of PIXE (particle induced X-ray emission) projections were taken in order to obtain information about the elemental distribution of the sample. From the PIXE projections the three-dimensional phosphorus distribution within the cell was reconstructed using limited-angle tomography. Superimposition of the STIM and PIXE tomograms revealed the location of intracellular structures. Whereas STIM tomography is sensitive to density contrast, which are greatest at the surface, PIXE tomography is sensitive to changes in elemental concentration. Hence, the combination of the two methods can be very fruitful, while the limited angle approach can compensate some of the difficulties associated with tomography of single cells, namely preparation difficulties and excessive sample damage.

PIXE was adopted for analysis of trace elements in teeth of two species of cetaceans, sperm whale (Physeter microcephalus) and pantropical spotted dolphin (Stenella attenuata). The analyses were performed along with the growth layer of the teeth, which is formed annually, suitable for age determination. Mn, Fe, Cu, Zu and Sr were detected in the teeth of sperm whale and pantropical spotted dolphin. Among these trace elements, gradual increase was observed for Zn/Ca ratio in the sperm whale's teeth. (author)

A study of the elemental concentrations of sediments of the rivers Tinto and Odiel, in Huelva, Spain, has been performed using PIXE. Thirteen samples have been collected, seven in the Tinto and six in the Odiel. Concentrations of 19 elements have been determined in each of them. The analysis of the data illustrates the environmental impact of the mining and fertilizer plants in the area. (orig.)

The trace element accumulating and integrating properties of epiphytic lichens were used for the study of air pollutions in Southern Poland. For the investigation of fluorine pollution by an aluminium plant the 19 F(p, p'γ) 19 F nuclear reaction, whereas for Pb and Br traffic pollution and heavy elements industrial pollution the PIXE method was used. The applicability of the lichen indicator method in environmental studies is discussed. (orig.)

The potential of using dried algae as a novel preconcentration technique for the analysis of water samples by PIXE was examined. 5 mg of dried algae powder were mixed with 5 mL of single- and multi-metal solutions. The algae cells were then collected by filtration on 0.6 um polycarbonate membranes and analyzed by PIXE using a dual energy irradiation. When C. vulgatis was used on mixed metal solutions, linear responses were observed for Ag + , Ba 2+ , and Cd 2+ in the concentration range from 10 ng/g to 1 ug/g; for Cu 2+ and Pb 2+ from 10 ng/g to 5 ug/g; and for Hg 2+ from 10 ng/g to 10 ug/g. When S. bacillaris was used, linear responses were observed from 10 ng/g up to 10 ug/g for all of the metal cations investigated. The PIXE results demonstrated that metal binding at low concentrations involves replacement of sodium on the cell wall and that at high concentrations magnesium is also replaced

Automated, nonbiased, multivariate statistical analysis techniques are useful for converting very large amounts of data into a smaller, more manageable number of chemical components (spectra and images) that are needed to describe the measurement. We report the first use of the multivariate spectral analysis program AXSIA (Automated eXpert Spectral Image Analysis) developed at Sandia National Laboratories to quantitatively analyze micro-PIXE data maps. AXSIA implements a multivariate curve resolution technique that reduces the spectral image data sets into a limited number of physically realizable and easily interpretable components (including both spectra and images). We show that the principal component spectra can be further analyzed using conventional PIXE programs to convert the weighting images into quantitative concentration maps. A common elemental data set has been analyzed using three different PIXE analysis codes and the results compared to the cases when each of these codes is used to separately analyze the associated AXSIA principal component spectral data. We find that these comparisons are in good quantitative agreement with each other

The innovative GridPix detector is a Time Projection Chamber (TPC) that is read out with a Timepix-1 pixel chip. By using wafer post-processing techniques an aluminium grid is placed on top of the chip. When operated, the electric field between the grid and the chip is sufficient to create electron induced avalanches which are detected by the pixels. The time-to-digital converter (TDC) records the drift time enabling the reconstruction of high precision 3D track segments. Recently GridPixes were produced on full wafer scale, to meet the demand for more reliable and cheaper devices in large quantities. In a recent beam test the contribution of both diffusion and time walk to the spatial and angular resolutions of a GridPix detector with a 1.2 mm drift gap are studied in detail. In addition long term tests show that in a significant fraction of the chips the protection layer successfully quenches discharges, preventing harm to the chip

The innovative GridPix detector is a Time Projection Chamber (TPC) that is read out with a Timepix-1 pixel chip. By using wafer post-processing techniques an aluminium grid is placed on top of the chip. When operated, the electric field between the grid and the chip is sufficient to create electron induced avalanches which are detected by the pixels. The time-to-digital converter (TDC) records the drift time enabling the reconstruction of high precision 3D track segments. Recently GridPixes were produced on full wafer scale, to meet the demand for more reliable and cheaper devices in large quantities. In a recent beam test the contribution of both diffusion and time walk to the spatial and angular resolutions of a GridPix detector with a 1.2 mm drift gap are studied in detail. In addition long term tests show that in a significant fraction of the chips the protection layer successfully quenches discharges, preventing harm to the chip.

We had the opportunity to study a large panel (100x80cm) containing more than 40 stained glass pieces. Among them several come from restorations having taken place at different periods. The study of this rather complex arrangement has been processed by stages:- the elemental composition of 16 zones were determined: several differences were identified and among them the Na/K ratio which allowed to set three groups of glass type; - the measurement of the Na concentrations by the two techniques give information in bulk (PIGE) and at the near surface (PIXE); the values defined by the (C PIGE -C PIXE) )/C PIGE plotted in function of the historical estimation of the age of the stained glass pieces (original and restored) indicate a real correlation between the two variables; - the red-colored pieces were specially investigated in order to determine which coloration technique was employed (bulk coloration, superficial staining, multilayered flashing, etc.); - the corrosion was investigated by scanning two different worsened zones with a 0.5mm diameter beam spot. This study shows the possibilities of the PIGE-PIXE association, but also points out some weaknesses, which have to be solved by other techniques; unfortunately, in that case, the non-destructive aspect could be lost

The elemental composition of healthy and diseased teeth from 25 South Australian children have been determined using thick target PIXE analysis. Different dental hard tissues, namely enamel, dentine, cementum and the amelodentinal junction, were analysed independently. A number of elements, Na, Mg, Al, P, S, Cl, Ca, V, Cr, Mn, Fe, Ni, Cu, Zn, Sr and Pb have been detected, and their concentrations measured. The concentrations of some of the elements were found to very considerable between: (a) healthy and diseases teeth, (b) teeth of the same type, and (c) different parts of the same tooth. Attemps have been made to correlate the concentrations of the various elements with the health of the teeth. In a pilot study, PIXE has also been applied for Pb analysis in the teeth of a few mentally retarded children. The teeth of all the children, with the exception of one who was suffering from Downe's syndrome, were found to contain appreciable amounts of lead. It is suggested that PIXE would provide a more convenient and accurate form of analysis than destructive chemical methods, for correlation Pb in children's teeth with their mental abilities. (orig.)

The micro-PIXE and RBS techniques are used to investigate the matrix as well as the trace elemental composition of calcium-rich human tissues on a microscopic scale. This paper deals with the spatial distribution of trace metals in hard human tissues such as kidney stone concretions, undertaken at the nuclear microprobe (NMP) facility. Relevant information about ion beam techniques used for material characterization will be discussed. Mapping correlation between different trace metals to extract information related to micro-regions composition will be illustrated with an application using proton energies of 1.5 and 3.0 MeV and applied to a comparative study for human kidney stone concretions nucleation region analysis from two different population groups (Sudan and South Africa)

Concentrations of trace elements in the whole blood, plasma and erythrocytes of 77 individuals (20 carrying the HbSS genotype, 21 with HbAS and 36 with HbAA) were determined using a PIXE facility employing a 2 MeV proton beam. Up to 16 elements were detected in some or all of the samples. The skewness of elemental distribution was measured for each element in the three bloodflow compartments. Most of the essential elements, apart from selenium were distinctly packed in either the erythrocytes or the plasma. Results of the t-test employed to compare elemental values between sickle cell subjects and matched controls show similar patterns in the three compartments for some of the elements. The results are compared with previous work using INAA. (orig.)

Proton therapy has become a subject of considerable interest in the radiation oncology community and it is expected that there will be a substantial growth in proton treatment facilities during the next decade. I was asked to write a historical review of proton therapy based on my personal experiences, which have all occurred in the United States, so therefore I have a somewhat parochial point of view. Space requirements did not permit me to mention all of the existing proton therapy facilities or the names of all of those who have contributed to proton therapy. (review)

A database of PIXE data, which have been accumulated at NMCC, has been constructed. In order to fill up the database, data are newly obtained as many as possible for the kind of samples whose number is small. In addition, the data for different measuring conditions are obtained for several samples. As the number of γ-ray spectrum obtained with a HPGe detector for the purpose of analyzing light elements such as fluorine, is overwhelmingly small in comparison with that of usual PIXE spectra, γ-ray spectrum and elemental concentration of fluorine are obtained as many as possible for food, environmental and hair samples. In addition, the data taken with an in-air PIXE system have been obtained for various samples. As a result, the database involving contents over various research fields is constructed, and it is expected to be useful for researches who make use of analytical techniques. It is expected that this work will give a start to many researchers to participate in the database and to make calibration with each other in order to establish reliable analytical techniques. Moreover, the final goal of the database is to establish the control concentration values for typical samples. As the first step of establishing the control values, average elemental concentration and its standard deviations in hair samples taken from 405 healthy Japanese are obtained and tabulated according to their sex and age. (author)

The main purpose of this project is the precise ion measurement of proton beam energy extracted at RF 25.89 MHz from the MC-50 cyclotron of SF type. There are several method for particle energy measurement. We measured the 50 MeV proton energy by using the E-{Delta}E method in 1993. And also in our experiment used range, reapproval of energy of extracted proton beam at RF 25.89 MHz was performed, which attained the same energy with the result used elastic scattering within the error range. 10 figs, 2 pix, 3 tabs, 3 refs. (Author).

We demonstrate the stereo-PIXE method by measurement of surface topography of the relief details on 1€ coin. Two X-ray elemental maps were simultaneously recorded by two X-ray detectors positioned at the left and the right side of the proton microbeam. The asymmetry of the yields in the pixels of the two X-ray maps occurs due to different photon attenuation on the exit travel path of the characteristic X-rays from the point of emission through the sample into the X-ray detectors. In order to calibrate the inclination angle with respect to the X-ray asymmetry, a flat inclined surface model was at first applied for the sample in which the matrix composition and the depth elemental concentration profile is known. After that, the yield asymmetry in each image pixel was transferred into corresponding local inclination angle using calculated dependence of the asymmetry on the surface inclination. Finally, the quantitative topography profile was revealed by integrating the local inclination angle over the lateral displacement of the probing beam

PIXE technique was employed to estimate the trace elemental concentrations in the biological samples of cancerous penis and testis. A 3 MeV proton beam was employed to excite the samples. From the present results it can be seen that the concentrations of Cl, Fe and Co are lower in the cancerous tissue of the penis when compared with those in normal tissue while the concentrations of Cu, Zn and As are relatively higher. The concentrations of K, Ca, Ti, Cr, Mn, Br, Sr and Pb are in agreement within standard deviations in both cancerous and normal tissues. In the cancerous tissue of testis, the concentrations of K, Cr and Cu are higher while the concentrations of Fe, Co and Zn are lower when compared to those in normal tissue of testis. The concentrations of Cl, Ca, Ti and Mn are in agreement in both cancerous and normal tissues of testis. The higher levels of Cu lead to the development of tumor. Our results also support the underlying hypothesis of an anticopper, antiangiogenic approach to cancer therapy. The Cu/Zn ratios of both penis and testis were higher in cancer tissues compared to that of normal.

Human hairs of cirrhosis, acute viral hepatitis patients and healthy people in Ulaanbaatar, capital city of Mongolia, were analyzed for the presence of heavy elements by PIXE spectrometry using 2.5 MeV proton beam at the Tokyo Institute of Technology Van de Graaff Laboratory. The samples were dissolved in a mixture of nitric acid and hydrogen peroxide. Then a 20μl aliquot was dropped on a Nuclepore Track-etch Membrane. The IAEA Reference Hair IAEA-086 certified reference material was used in order to verify accuracy of the method and the results were in good agreement with the certified values. To determine the interaction among nine elements in hair, correlation coefficients were evaluated for several pairs of elements. in the group of healthy control, no correlation between elements was identified. Opposite to this, the strong positive correlations were observed for Zn and Ca or Fe; Mn and Ca or Ti; Sr and Zn or Fe in the patients hair. In the present study, the mean concentrations of Ca, Ti, As and Sr in Mongolian patients were higher than those in the hair of normal people in Japan, Mongolia, Iran and Indonesia. The levels of Cu, Zn and Mn concentration in hair of normal people were almost the same for all the cohorts. (Author)

Volcanic deposits from two volcanic districts, Monti Sabatini (MSVD) and Colli Albani (CAVD), NW and SE of Rome, were analyzed using the particle-induced X-ray emission (PIXE) technique, in order to obtain chemical fingerprints that can be used for provenance studies of filler materials in ancient Roman mortars. The rock samples were mounted on an X-Y stage enabling scanning over the sample surface and irradiated in air with a collimated 3 MeV proton beam. The samples were either analyzed by scanning the beam over a polished surface or they were crushed, ground and homogenized prior to the irradiation. However, scanning over polished sample surfaces avoiding heterogeneities gave quite similar results as scanning over pellet surfaces, especially for the minor and trace elements. This study shows that the deposits of MSVD and CAVD can be distinguished from each other. Several elements or elemental ratios can be used to characterize the districts. Even the individual volcanic deposits of CAVD can be identified

Micro Proton Induced X-ray Emission (μ-PIXE) analysis has been employed herein in investigating and quantifying the distribution of a number of essential cations in two thin slices of normal and diseased human articular cartilage, the latter being affected by osteoarthritis (OA). The elemental distribution maps for Ca, P, K, S and Zn in the normal and diseased slices showed similar patterns with marked increases in elemental concentrations in the bone-cartilage interface. The S concentration was significantly lower in bone than in cartilage. Conversely, the Ca and P concentrations were higher in bone. The Ca/P ratio (2.22) of the diseased slice was determined by employing the Rutherford backscattering technique (RBS). The RBS figures of this investigation agree with values previously reported by others. Structural and organisational changes of collagen networks were investigated by coherent Small-Angle X-ray Scattering (SAXS) using beamline facilities at the Swiss Light Source (SLS) for a decalcified diseased human articular cartilage slice. The SAXS findings showed a gradual reorientation of collagen type II fibres of cartilage from parallel to the surface of the joint to normal to the bone-cartilage interface. Similar patterns of orientation were observed at the subchondral bone to bone-cartilage interface

Full text: Diabetes mellitus, a metabolic disease characterized by high blood glucose levels (hyperglycemia) due to defects in insulin secretion, or action, or both. It is a dangerous disease leading to death of many people in the world. Some of the medicinal plants implicated in the herbal recipes for the treatment of diabetes in Nigeria have been reported 1 . Additional medicinal plants used for the treatment of diabetes in Nigeria are presented in this work. These medicinal plants are becoming increasingly important and relevant as herbal drugs due to their use as antioxidants, neutraceuticals, food additives and supplements in combating diabetes. Elemental compositions of these anti-diabetic medicinal plants were determined using PIXE technique. The 1.8 MV collimated proton beam from the 2.5 MV AN 2000 Van de Graaff accelerator at Instituto Nazionale di Fisica Nucleare (INFN), Laboratori Nazionali di Legnaro (LNL) Legnaro (Padova) Italy was employed for the work. The results show the presence of twenty two elements at various concentrations in the medicinal plants. The leaves of Murraya, P amarus, O. gratissimum, O.subscopodica, P pellucida and the whole plant of B. diffusa, B. pinnalum and C. occidenlalis could be taken as vegetables, food additives, neutraceuticals and supplements in the management of diabetes. [1] S.O. Olabanji, OR Omobuwajo, D. Ceccato, A.C. Adebajo, M.C. Buoso, G. Moschini. Nucl. Instrum. Methods Phys. Res. Sect. B 266 (2008) 2387 - 2390. (author)

To obtain Pt concentration distributions in tumor biopsies, micro-PIXE is used. The limit of detection (LOD) for Pt is determined by the background production cross section together with the production cross section for the Pt-L lines. Both are functions of the type and energy of the projectile. In order to optimise the experimental conditions, the proton energy is varied from 2.5 to 5 MeV and the corresponding X-ray spectra are analysed. The optimum LOD is about 1 μg/g for a sample thickness of 1 mg/cm 2 and a total charge of 100 μC. A study is performed to investigate the possibility of elemental analysis by means of α excitation. The corresponding LOD is 6 μg/g with 200 μC charge (He ++ was used). For α excitation, sample damage limits the beam current and, thus, causes a tremendous increase in the measurement time. (orig.)

Full text: Diabetes mellitus, a metabolic disease characterized by high blood glucose levels (hyperglycemia) due to defects in insulin secretion, or action, or both. It is a dangerous disease leading to death of many people in the world. Some of the medicinal plants implicated in the herbal recipes for the treatment of diabetes in Nigeria have been reported{sup 1}. Additional medicinal plants used for the treatment of diabetes in Nigeria are presented in this work. These medicinal plants are becoming increasingly important and relevant as herbal drugs due to their use as antioxidants, neutraceuticals, food additives and supplements in combating diabetes. Elemental compositions of these anti-diabetic medicinal plants were determined using PIXE technique. The 1.8 MV collimated proton beam from the 2.5 MV AN 2000 Van de Graaff accelerator at Instituto Nazionale di Fisica Nucleare (INFN), Laboratori Nazionali di Legnaro (LNL) Legnaro (Padova) Italy was employed for the work. The results show the presence of twenty two elements at various concentrations in the medicinal plants. The leaves of Murraya, P amarus, O. gratissimum, O.subscopodica, P pellucida and the whole plant of B. diffusa, B. pinnalum and C. occidenlalis could be taken as vegetables, food additives, neutraceuticals and supplements in the management of diabetes. [1] S.O. Olabanji, OR Omobuwajo, D. Ceccato, A.C. Adebajo, M.C. Buoso, G. Moschini. Nucl. Instrum. Methods Phys. Res. Sect. B 266 (2008) 2387 - 2390. (author)

Micro Proton Induced X-ray Emission (μ-PIXE) analysis has been employed herein in investigating and quantifying the distribution of a number of essential elements in thin human diseased articular cartilage sections affected by osteoarthritis (OA). Various cations Ca, P and Zn have been reported to play an important role both in the normal growth and remodelling of articular cartilage and subchondral bone as well as in the degenerative and inflammatory processes associated with the disease; they act as co-factors of a class of enzymes known as metalloproteinases which are believed to be active during the initiation, progress and remodelling processes associated with osteoarthritis. Other important enzymes such as alkaline phosphatase are associated with cartilage mineralization. Synchrotron radiation X-ray fluorescence (SR-XRF) for mapping of elemental distributions in bone and cartilage has also been employed by the present group and others. In the current investigations using the cSAXS beamline at the Swiss light source, Small-Angle X-ray Scattering (SAXS) was carried out on decalcified human articular cartilage to explore the structural and organizational changes of collagen networks in diseased articular cartilage.

Micro Proton Induced X-ray Emission ({mu}-PIXE) analysis has been employed herein in investigating and quantifying the distribution of a number of essential elements in thin human diseased articular cartilage sections affected by osteoarthritis (OA). Various cations Ca, P and Zn have been reported to play an important role both in the normal growth and remodelling of articular cartilage and subchondral bone as well as in the degenerative and inflammatory processes associated with the disease; they act as co-factors of a class of enzymes known as metalloproteinases which are believed to be active during the initiation, progress and remodelling processes associated with osteoarthritis. Other important enzymes such as alkaline phosphatase are associated with cartilage mineralization. Synchrotron radiation X-ray fluorescence (SR-XRF) for mapping of elemental distributions in bone and cartilage has also been employed by the present group and others. In the current investigations using the cSAXS beamline at the Swiss light source, Small-Angle X-ray Scattering (SAXS) was carried out on decalcified human articular cartilage to explore the structural and organizational changes of collagen networks in diseased articular cartilage.

Melanoma is a serious and deadly form of skin cancer. However, patients' chances of survival and recovery are considerably increased when it is diagnosed and treated in its early stages. In this study, trace element concentrations in serum samples from patients with melanoma were measured using PIXE (Proton Induced X-ray Emission) and HR-ICPMS (High-Resolution Inductively Coupled Plasma Mass Spectrometry), with the purpose of correlating these concentrations with the disease. Blood samples from 30 melanoma patients and 116 healthy donors were collected at São Paulo Hospital (protocol CEP 1036/08 UNIFESP). Relevant clinical information on the patients has also been included in the statistical analysis. Analysis of the control group showed different P and Mg concentrations in individuals above and below 40 years of age. P, S, Ca, Cu and Zn concentrations in healthy individuals differed according to gender, highlighting the necessity to include age and gender variables in the case-control analysis. There were also differences in K, S, Ca and Se concentrations between the control and melanoma groups.

Melanoma is a serious and deadly form of skin cancer. However, patients’ chances of survival and recovery are considerably increased when it is diagnosed and treated in its early stages. In this study, trace element concentrations in serum samples from patients with melanoma were measured using PIXE (Proton Induced X-ray Emission) and HR-ICPMS (High-Resolution Inductively Coupled Plasma Mass Spectrometry), with the purpose of correlating these concentrations with the disease. Blood samples from 30 melanoma patients and 116 healthy donors were collected at São Paulo Hospital (protocol CEP 1036/08 UNIFESP). Relevant clinical information on the patients has also been included in the statistical analysis. Analysis of the control group showed different P and Mg concentrations in individuals above and below 40 years of age. P, S, Ca, Cu and Zn concentrations in healthy individuals differed according to gender, highlighting the necessity to include age and gender variables in the case-control analysis. There were also differences in K, S, Ca and Se concentrations between the control and melanoma groups.

Abstract Dicranogonus pix Jeekel, 1982 occurs in Victoria and Tasmania, Australia, including the islands in eastern Bass Strait between the two States. There is only slight gonopod variation across this range, but Dicranogonus pix populations with and without paranota are separated in Bass Strait by the ca 50 km-wide gap between the Kent and Furneaux Groups of islands. PMID:25493065

The main purpose of this analysis was to determine whether nickel is present in diamond powder as a trace element. Particle induced X-ray emission (PIXE) showed unambiguously that nickel was present. Due to the convenience of PIXE in multielemental analysis, the investigations also include a number of other trace elements in the sample

Metal fiducial markers are often implanted on the back of the eye before proton therapy to improve target localization and reduce patient setup errors. We aim to detect characteristic x-ray emissions from metal targets during proton therapy to verify the treatment range accuracy. Initially gold was chosen for its biocompatibility properties. Proton-induced x-ray emissions (PIXE) from a 15 mm diameter gold marker were detected at different penetration depths of a 59 MeV proton beam at the CATANA proton facility at INFN-LNS (Italy). The Monte Carlo code Geant4 was used to reproduce the experiment and to investigate the effect of different size markers, materials, and the response to both mono-energetic and fully modulated beams. The intensity of the emitted x-rays decreases with decreasing proton energy and thus decreases with depth. If we assume the range to be the depth at which the dose is reduced to 10% of its maximum value and we define the residual range as the distance between the marker and the range of the beam, then the minimum residual range which can be detected with 95% confidence level is the depth at which the PIXE peak is equal to 1.96 σ bkg , which is the standard variation of the background noise. With our system and experimental setup this value is 3 mm, when 20 GyE are delivered to a gold marker of 15 mm diameter. Results from silver are more promising. Even when a 5 mm diameter silver marker is placed at a depth equal to the range, the PIXE peak is 2.1 σ bkg . Although these quantitative results are dependent on the experimental setup used in this research study, they demonstrate that the real-time analysis of the PIXE emitted by fiducial metal markers can be used to derive beam range. Further analysis are needed to demonstrate the feasibility of the technique in a clinical setup. (paper)

A "milliprobe" system was implemented by using the focusing properties of a Van de Graaff accelerator, together with a collimator system including 1 mm diameter apertures, to impose the appropriate dimension to the beam spot. The scanning of the sample surface was achieved by X-Y movements of the sample holder (the Z axis being coincident with the beam direction). These movements were accomplished by a motorised X-Y table, with a travel of 25 mm × 25 mm, connected to the sample holder. This system was used to study specimens of the mineral tourmaline. Two samples, of the "watermelon" zoned tourmaline variety, originating from the Alto Ligonha pegmatite district in northern Mozambique, were analysed by the simultaneous use of PIXE (Proton-Induced X-Ray Emission) and PIGE (Proton-Induced Gamma-Ray Emission) techniques, in order to quantify their composition and try to establish a correlation between the elements (major and trace elements) and colour zoning. In order to validate the "milliprobe" analysis and study in more detail the frontier between zones of different colours, a microprobe analysis of the samples was also done. In this work, the mineralogical classification of the samples was accomplished. A correlation was established between the presence of Fe and green colour. It was also concluded that the presence of Mn by itself is not enough to lead to pink colour, which gives support to previous studies that claim that only Mn3+ and not the more common form Mn2+ is responsible for the pink colour.

A 'milliprobe' system was implemented by using the focusing properties of a Van de Graaff accelerator, together with a collimator system including 1mm diameter apertures, to impose the appropriate dimension to the beam spot. The scanning of the sample surface was achieved by X-Y movements of the sample holder (the Z axis being coincident with the beam direction). These movements were accomplished by a motorised X-Y table, with a travel of 25mmx25mm, connected to the sample holder. This system was used to study specimens of the mineral tourmaline. Two samples, of the 'watermelon' zoned tourmaline variety, originating from the Alto Ligonha pegmatite district in northern Mozambique, were analysed by the simultaneous use of PIXE (Proton-Induced X-Ray Emission) and PIGE (Proton-Induced Gamma-Ray Emission) techniques, in order to quantify their composition and try to establish a correlation between the elements (major and trace elements) and colour zoning. In order to validate the 'milliprobe' analysis and study in more detail the frontier between zones of different colours, a microprobe analysis of the samples was also done. In this work, the mineralogical classification of the samples was accomplished. A correlation was established between the presence of Fe and green colour. It was also concluded that the presence of Mn by itself is not enough to lead to pink colour, which gives support to previous studies that claim that only Mn{sup 3+} and not the more common form Mn{sup 2+} is responsible for the pink colour.

Five species of rodents have been collected in an area near Lake Powell Utah. Common names of the five species are: Long-tailed Mouse, Small Pocket Mouse, Deer Mouse, Antelope Ground Squirrel and Kangaroo Rat. Liver, lung, kidney and hair tissues from each animal were analyzed for trace element content by proton particle-induced x-ray emission (protonPIXE) analysis. Mean concentrations for the following elements were established for the tissues of each animal type: K, Ca, Ti, Mn, Fe, Ni, Cu, Zn, Se, Br, Rb and Pb. Analyses of variance were performed on the set of elements common to all tissues. Some significant differences in element concentrations were found between animal species and between tissue types. These differences lead to the following orders based on element concentration: Long-tailed Mouse greater than or equal to Antelope Ground Squirrel greater than or equal to Kangaroo Rat greater than or equal to Small Pocket Mouse and liver greater than or equal to kidney greater than or equal to lung greater than or equal to hair. Linear regression analyses were also performed on mean elemental concentrations in tissues. These analyses lead to several conclusions. First, the pattern of trace element concentrations in each of the four tissues is the same in all five species. Second, the pattern of trace element concentrations is the same in all four tissues of one species with the exception of Ti and Fe in hair. Third, the variation of an element in the hair cannot predict the variation of that same element in the other three tissues. Only K, Ca, Ti, Mn, Fe, Cu, and Zn were included in the third study

Full text: The study of cultural heritage of ancient people through fossils, monuments and engines has fundamental importance in the construction of the memory of any society. Such knowledge can be acquired by researches in archaeological sites and the detailed study of the different kind of objects which can be found in these places. This work deals with objects from the Sambaqui of Panaquatira located in Sao Luis do Maranhao (Brazil). Ancient civilizations that inhabited that territory were characterized as fishing populations - catchers - hunters and ceramists. From a selection of 95 pottery fragments of surface; 5 to 10 cm; 20 to 30 cm; 40 to 50 cm; 65 to 70 cm; 80 to 90 cm; 90 to 100 cm; 130 to 140 cm and 160 to 170 cm stratigraphic levels, a representative set was analyzed using Particle Induced X-ray Emission (PIXE) methodology. PIXE measurements were performed with an external beam setup with ~2.4 MeV proton beam in the LAMFI laboratory using three X-ray detectors, two Si-PIN detectors and one HPGe with standard spectrometry electronics; each spectrum was taken for 600s. The spectra analyses were performed with the Quantitative X-Ray Analysis Software (WinQXAS), distributed by International Atomic Energy Agency (IAEA). The elements Si, P, S, CI, K, Ca, Ti, Cr, Mn, Fe and Zn were identified in the different fragments. It was analysed the kind of applied treatment on the concave and convex sides in relation to the ceramic paste of the fragments. From the determination of the elemental composition of the fragments, it was possible to identify that the elements Ti, Mn, Fe and Zn are present in the fragments with larger amounts at concave and convex sides, compared to the ceramic paste, indicating a different surface treatment that leads to an enrichment of these elements. One fragment from the 20-25cm stratigraphy has a lighter colour region which is characterized by containing the highest concentration of the elements Ti, Ca, Ti, Cr and Mn. (author)

Full text: The study of cultural heritage of ancient people through fossils, monuments and engines has fundamental importance in the construction of the memory of any society. Such knowledge can be acquired by researches in archaeological sites and the detailed study of the different kind of objects which can be found in these places. This work deals with objects from the Sambaqui of Panaquatira located in Sao Luis do Maranhao (Brazil). Ancient civilizations that inhabited that territory were characterized as fishing populations - catchers - hunters and ceramists. From a selection of 95 pottery fragments of surface; 5 to 10 cm; 20 to 30 cm; 40 to 50 cm; 65 to 70 cm; 80 to 90 cm; 90 to 100 cm; 130 to 140 cm and 160 to 170 cm stratigraphic levels, a representative set was analyzed using Particle Induced X-ray Emission (PIXE) methodology. PIXE measurements were performed with an external beam setup with ~2.4 MeV proton beam in the LAMFI laboratory using three X-ray detectors, two Si-PIN detectors and one HPGe with standard spectrometry electronics; each spectrum was taken for 600s. The spectra analyses were performed with the Quantitative X-Ray Analysis Software (WinQXAS), distributed by International Atomic Energy Agency (IAEA). The elements Si, P, S, CI, K, Ca, Ti, Cr, Mn, Fe and Zn were identified in the different fragments. It was analysed the kind of applied treatment on the concave and convex sides in relation to the ceramic paste of the fragments. From the determination of the elemental composition of the fragments, it was possible to identify that the elements Ti, Mn, Fe and Zn are present in the fragments with larger amounts at concave and convex sides, compared to the ceramic paste, indicating a different surface treatment that leads to an enrichment of these elements. One fragment from the 20-25cm stratigraphy has a lighter colour region which is characterized by containing the highest concentration of the elements Ti, Ca, Ti, Cr and Mn. (author)

In this work we study hydroxyapatite, hydroxyapatite doped with zinc or manganese and the compound of 75% hydroxyapatite, 25% tricalcic phosphate. The ceramics were implanted in the cortical femur of sheep. The global evolution of mineral concentrations in the implants with the time after implantation was studied by neutronic radioactivation. We studied matrix effects in P.I.X.E. (Particles Induced X-rays Emission) with Alpha parameter method. By measurements at two different energies, we determine a correction factor of the slowing down of incident protons and of the X rays absorption in matrix. So, the P.I.X.E. analysis allow us a scanning of mineral concentrations at the bone-implant interface at different time after implantation. The transformation of the hydroxyapatite matrix has been studied by X-rays by X-rays diffraction. (author)

Lakes are ecosystems where there is a great potential of metal accumulation in sediments due to their depositional characteristics. Total concentration of trace elements was measured on a 50 cm long sediment core from the Infernao Lake, that is an oxbow lake of the Moji-Guacu River basin, in the state of Sao Paulo, Brazil. Dating of the core shows up to 180 yrs old sediment layers. The use of the PIXE technique for elemental analysis avoids the traditional acid digestion procedure common in other techniques. The multielemental characteristic of PIXE allows a simultaneous determination of about 20 elements in the sediment samples, such as, Al, Si, P, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Rb, Sr, Zr, Ba, and Pb. Average values for the elemental composition were found to be similar to the bulk crustal composition. The lake flooding pattern strongly influences the time series of the elemental profiles. Factor analysis of the elemental variability shows five factors. Two of the factors represent the mineralogical matrix, and others represent the organic component, a factor with lead, and another loaded with chromium. The mineralogical component consists of elements such as, Fe, Al, V, Ti, Mn, Ni, K, Zr, Sr, Cu and Zn. The variability of Si is explained by two distinct factors, because it is influenced by two different sources, aluminum-silicates and quartz, and the effect of inundation are different for each other. The organic matter is strongly associated with calcium, and also bounded with S, Zn, Cu and P. Lead and chromium appears as separated factors, although it is not clear the evidences for their anthropogenic origin. The techniques developed for sample preparation and PIXE analysis was proven as advantageous and provided very good reproducibility and accuracy

The PIXE method was applied to the analysis of trace elements in scalp hair using two methods for target preparation. In the first method eigth hair strands each with nearly cylindrical geommetry and approximately the same diameter were selected and placed on an aluminum frame. In the second method a given mass of hair was dissolved with nitric acid and a known amount of strontium was added to the solution and dripped on a membrane filter using a micropipet. The results for the concentrations of trace elements in hair obtained by the two methods are compared and several aspects of the analysis is discussed. (Author) [pt

Particle-induced x-ray emission (PIXE) and Rutherford backscattering spectrometry (RBS) were used to analyse desert rose geological samples. Samples from the rose core and from the rose peripherals were studied. All samples were found to contain C, N, O, Na, Mg, Si, S, Cl, K, Ca, Ti, Mn, Fe and Sr. Core samples were found to contain more silicon than peripheral samples. The extra silicon in the rose core may suggest a mechanism for the formation of the rose through crystal growth on a seed of silicon. (author)

PIXE was adopted to analyze trace elements in otoliths of Japanese flounder to discriminate among several local fish stocks. The otoliths were removed from samples caught at five different sea areas along with the coast of the Sea of Japan: Akita, Ishikawa, Kyoto (2 stations), and Fukuoka. Besides calcium as main component, strontium, manganese, and zinc were detected. Especially Sr concentrations were different among 4 areas except between 2 stations in Kyoto. It suggested that the fish in the 2 stations in Kyoto were the same stock differed to the others. (author)

Five copper alloys were prepared with modern powder metallurgical processes in the frame of the European project 'Improvement of Means of Measurement on Archaeological Copper-Alloys for Characterisation and Conservation (IMMACO)' and certified for As, Pb, Sn and Zn mass fractions. Similar in their composition to archaeological bronze alloys, these Certified Reference Materials (CRMs) are to be used for calibration of XRF instruments for characterization of archaeological samples either in the laboratory or in the field. Successful contribution of non-destructive analytical methods (k 0 -NAA and PIXE) to the IMMACO project and to the certification of the five reference materials is presented. (author)

The Japanese papers, 'washi', are made from the bast fibers of the plants. Since washi have the informations of the raw material plants, there is potentiality of the identification of the production place by the element analysis of the washi. Three kinds of washi made of kozo, which have different habitats, were prepared. The elements in their washi were measured by the PIXE. It was confirmed that the amount of elements included in the washi depend on the habitats of their raw material plants. (author)

Elemental analyses were carried out for the seabed sludge collected from Uranouchi bay (Kochi, Japan) using Particle Induced X-ray Emission (PIXE). Seabed-sludge contamination with heavy metals as well as toxic elements becomes one of the most serious environmental problems. The aim of the present study is to investigate the polluted areas in the bay by heavy and toxic elements. As a results of analyses of samples collected from eleven different places in the bay, seventeen elements including toxic ones were detected. The results suggest that the center region of the bay is seriously contaminated by heavy and toxic elements in comparison with the other areas in the bay. (author)

A method to apply particle induced X-ray emission (PIXE) for depth profiling, based on the variation of the X-ray detection angle, is proposed. The procedure uses X-ray yields normalized to those emitted at a particular reference angle. Application of the method to implanted samples and thin metallic films gave excellent results regarding the range of implanted ions and film thickness, respectively. However, there is no complete information about the width of the distribution of the implanted ions, emphasizing the need to develop a full mathematical algorithm to obtain the general depth profile

This paper reports the results about the PIXE analysis of major, minor and trace elements of Chinese ancient greenish white porcelain and blue-and-white porcelain produced in Hutian Kiln (Jingdezhen district, Jiangxi province) during 10th-14th centuries. The porcelain body and greenish white glaze from northern Song (AD 960), southern Song (AD 1037-1276), early Yuan (AD 1279-1320), later Yuan (AD 1320-1368) were investigated together with white-and-blue glaze from Ming dynasty (AD 1368-1644). The obtained data were further analyzed by factor analysis

Gemologists consider the mineral beryl, beryllium aluminium silicate, to be the gem, emerald, when it contains sufficient chromium, >0.1%, to colour it a strong green. Emeralds usually contain other trace elements. To investigate the feasibility of distinguishing an emerald's country of origin through its trace content, the trace elements in emeralds and a few beryls from sixteen locations have been determined with a single nondestructive measurement using PIXE and PIGE. From the database established with this limited number of samples, distinguishing trace element patterns were found. (orig.)

Considering methodology of PIXE quantitative analysis based on Inner-standard, we provide a simple and convenient method to measure the elemental relative sensitivity curve. The concentrations of 16 various elements in cerebrospinal fluid samples before and after brain transplantation have been investigated and compared with those of normal person's and transplanted tissues. The experimental results show that the brain transplantation results in apparently curative effects in compensating and regulating the element concentrations in cerebrospinal fluid and improvement of elemental physiological metabolism. It illustrates that the appropriate concentrations of trace elements in cerebrospinal fluid play an undoubtedly important role in keeping the normal physiological function of brain and central nervous system. (author)

This paper reports the results about the PIXE analysis of major, minor and trace elements of Chinese ancient greenish white porcelain and blue-and-white porcelain produced in Hutian Kiln (Jingdezhen district, Jiangxi province) during 10th-14th centuries. The porcelain body and greenish white glaze from northern Song (AD 960), southern Song (AD 1037-1276), early Yuan (AD 1279-1320), later Yuan (AD 1320-1368) were investigated together with white-and-blue glaze from Ming dynasty (AD 1368-1644). The obtained data were further analyzed by factor analysis.

This paper reports the results about the PIXE analysis of major, minor and trace elements of Chinese ancient greenish white porcelain and blue-and-white porcelain produced in Hutian Kiln (Jingdezhen district, Jiangxi province) during 10th-14th centuries. The porcelain body and greenish white glaze from northern Song (AD 960), southern Song (AD 1037-1276), early Yuan (AD 1279-1320), later Yuan (AD 1320-1368) were investigated together with white-and-blue glaze from Ming dynasty (AD 1368-1644). The obtained data were further analyzed by factor analysis.

In this work we study hydroxyapatite, hydroxyapatite doped with zinc or manganese and the compound of 75% hydroxyapatite, 25% tricalcic phosphate. The ceramics were implanted in the cortical femur of sheep. The global evolution of mineral concentrations in the implants with the time after implantation was studied by neutronic radioactivation. We studied matrix effects in P.I.X.E. (Particles Induced X-rays Emission) with Alpha parameter method. By measurements at two different energies, we determine a correction factor of the slowing down of incident protons and of the X rays absorption in matrix. So, the P.I.X.E. analysis allow us a scanning of mineral concentrations at the bone-implant interface at different time after implantation. The transformation of the hydroxyapatite matrix has been studied by X-rays by X-rays diffraction. (author).

Full text: Particle Induced X-ray Emission (PIXE)technique has been widely used since its birth for the study of the aerosol composition, and for a long time it has been the dominating technique for its elemental analysis. However now it has to compete with other techniques, like Induced Coupled Plasma and detection by Atomic Emission Spectroscopy (ICP-AES) or Mass Spectrometry (ICP-MS) or Synchrotron Radiation XRF (SR-XRF). To remain competitive, a proper experimental set-up is important to fully exploit PIXE capabilities. At LABEC, an external beam line is fully dedicated to PIXE-PIGE measurements of atmospheric aerosols [1]. Recently SDD (Silicon Drift Detectors) have been introduced for X-ray detection thanks to their better resolution with respect to Si(Li) detectors and the possibility of managing high counting rates (up to 50 kHz at 0.5 μsec shaping time). This implies, in turn, the possibility of using very high beam currents thus drastically reducing the measurement time. However their use for a complete characterization of X-rays was limited by the small thickness and surface areas available. Now SDD with a thickness of 500 μm and 80 mm{sup 2} area have been introduced in the market. We have therefore replaced the Si(Li) detector used so far for the detection of medium-high Z elements with such a SDD. A comparison of the two detectors has been carried out; PIXE minimum detection limits (MDLs) at different proton beam energies have been studied to find out the best energy for PIXE measurements on aerosol samples collected on different substrata, namely Teflon, Kapton, Nuclepore and Kimfol, used for daily or hourly sampling or for cascade impactors. In particular in the case of Teflon filters, the production of γ-rays by F in the Teflon filter limits the current which may be used and the Compton γ-ray background worsens the MDLs. Due to the lower thickness of the SDD detector with respect to a typical Si(Li) detector, these problems are reduced

Full text: Obsidian is the most important archaeological material used for tools and weapons before metals appearance. Its geological sources are limited and concentrated in few geographical zones: Armenia, Eastern Anatolia, Italian Lipari and Sardinia islands, Greek Melos and Yali islands, Hungarian and Slovak Tokaj Mountains. Due to this fact, in Mesolithic and Neolithic periods obsidian was the first archaeological material intensively traded even at long distances. To determine the geological provenance of obsidian and to identify the prehistoric long-range trade routes and possible population migrations elemental concentration ratios can help a 101, since each geological source has its 'fingerprints'. In this work external milli-PIXE technique was applied for elemental concentration ratio determinations in some Neolithic tools found in Transylvania and in the lron Gales region near Danube, and on few relevant geological samples (Slovak Tokaj Mountains, Lipari,Armenia). In Transylvania (the North-Western part of Romania, a region surrounded by Carpathian Mountains), Neolithic obsidian tools were discovered mainly in three regions: North-West - Oradea (near the border with Hungary, Slovakia and Ukraine), Centre -Cluj and Southwest- Banat (near the border with Serbia). A special case is lron Gales - Mesolithic and Early Neolithic sites, directly related to the appearance of agriculture replacing the Mesolithic economy based on hunting and fishing. Three long-distance trade routes could be considered: from Caucasus Mountains via North of the Black Sea, from Greek islands or Asia Minor via ex-Yugoslavia area or via Greece-Bulgaria or from Central Europe- Tokaj Mountains in the case of obsidian. As provenance 'fingerprints', we focused on Ti to Mn, and Rb-Sr-Y-Zr ratios. The measurements were performed at the external milli-PIXE beam-line of the 5MV VdG accelerator of the Wigner RCP. Proton energy of 3MeV and beam currents in the range of 1 ±1 D

Full text: Obsidian is the most important archaeological material used for tools and weapons before metals appearance. Its geological sources are limited and concentrated in few geographical zones: Armenia, Eastern Anatolia, Italian Lipari and Sardinia islands, Greek Melos and Yali islands, Hungarian and Slovak Tokaj Mountains. Due to this fact, in Mesolithic and Neolithic periods obsidian was the first archaeological material intensively traded even at long distances. To determine the geological provenance of obsidian and to identify the prehistoric long-range trade routes and possible population migrations elemental concentration ratios can help a 101, since each geological source has its 'fingerprints'. In this work external milli-PIXE technique was applied for elemental concentration ratio determinations in some Neolithic tools found in Transylvania and in the lron Gales region near Danube, and on few relevant geological samples (Slovak Tokaj Mountains, Lipari,Armenia). In Transylvania (the North-Western part of Romania, a region surrounded by Carpathian Mountains), Neolithic obsidian tools were discovered mainly in three regions: North-West - Oradea (near the border with Hungary, Slovakia and Ukraine), Centre -Cluj and Southwest- Banat (near the border with Serbia). A special case is lron Gales - Mesolithic and Early Neolithic sites, directly related to the appearance of agriculture replacing the Mesolithic economy based on hunting and fishing. Three long-distance trade routes could be considered: from Caucasus Mountains via North of the Black Sea, from Greek islands or Asia Minor via ex-Yugoslavia area or via Greece-Bulgaria or from Central Europe- Tokaj Mountains in the case of obsidian. As provenance 'fingerprints', we focused on Ti to Mn, and Rb-Sr-Y-Zr ratios. The measurements were performed at the external milli-PIXE beam-line of the 5MV VdG accelerator of the Wigner RCP. Proton energy of 3MeV and beam currents in the range of 1 ±1 D

This paper describes the standardization of the proton-induced x-ray emission (PIXE) technique for finding the elemental composition of thick samples. For the standardization, three different samples of standard reference materials (SRMs) were analyzed using this technique and the data were compared with the already known data of these certified SRMs. These samples were selected in order to cover the maximum range of elements in the periodic table. Each sample was irradiated for three different values of collected beam charges at three different times. A proton beam of 2.57 MeV obtained using 5UDH-II Pelletron accelerator was used for excitation of x-rays from the sample. The acquired experimental data were analyzed using the GUPIXWIN software. The results show that the SRM data and the data obtained using the PIXE technique are in good agreement.

This experimental study consists in make falling a particle beam on a collected sample of the air pollutants. In the present work protons coming from a particle accelerator were used. The magnet baffle of this it selects the protons energy according to the experiment. The beam current is generally of the order of nano amperes and it can be measured and integrated. At the interact the beam with the sample there are produced X rays characteristic of each one of those present elements in it. These X rays are registered by a Li-Si detector of which proportional pulses are obtained to the energy of the same ones. Finally this pulses are electronically processed in a typical arrangement (preamplifier-amplifier-multichannel) that delivers an energy spectra characteristic of the sample elements. Each one of the peaks of the spectra represents an element which is possible to identify. From the under curve area of each peak it can be evaluated the concentration corresponding to each element. (Author)

The objectives of this work are: to identify the heavy metals present in the air, and its concentrations. To know the behavior from the polluting chemical elements to the long of an annual cycle corresponding to 1990, based on the concentrations of the same ones, obtained through the PIXE technique. To identify the suitable statistical methods to use to the data of metals concentration in form of total suspended particle (PST), found in this investigation. To relate the concentrations and the meteorological parameters considered to be able to suggest the possible pollution sources. In function of the obtained results, to serve as base to the decisions making and measures control that are planned by diverse institutions focused to the problem of the atmospheric pollution in the Metropolitan area of Mexico City (ZMCM). (Author)

Most air quality studies on particulate matter (PM) are based on 24-h averaged data; however, many PM emissions as well as their atmospheric dilution processes change within a few hours. Samplings of PM with 1-h resolution can be performed by the streaker sampler (PIXE International Corporation), which is designed to separate the fine (aerodynamic diameter less than 2.5 μm) and the coarse (aerodynamic diameter between 2.5 and 10 μm) fractions of PM. These samples are efficiently analyzed by Particle Induced X-ray Emission (PIXE) at the LABEC laboratory of INFN in Florence (Italy), equipped with a 3 MV Tandetron accelerator, thanks to an optimized external-beam set-up, a convenient choice of the beam energy and suitable collecting substrates. A detailed description of the adopted set-up and results from a methodological study on the detection limits for the selection of the optimal beam energy are shown; the outcomes of the research on alternative collecting substrates, which produce a lower background during the measurements, and with lower contaminations, are also discussed.

The potential of using dried algae as a novel preconcentration technique for the analysis of water samples by PIXE was examined. The algae cells were found to contain significant levels of P and S, indicative of phosphorous- and sulfur-containing groups on the cell wall or inside the algae cells which may serve as potential binding sites for metal ions. When C. vulgaris was used on mixed metal solutions, linear responses were observed for Ag + , Ba 2+ , and Cd 2+ in the concentration range from 10 ng/g to 1 μg/g; for Cu 2+ and Pb 2+ from 10 ng/g to 5 μg/g; and for Hg 2+ from 10 ng/g to 10 μg/g. When S. bacillaris was used, linear responses were observed from 10 ng/g up to 10 μg/g for all of the metal cations investigated. The PIXE results demonstrated that metal binding at low concentrations involves replacement of sodium on the cell wall and that at high concentrations magnesium was also replaced. Competitive binding studies indicate that the metal ions, Ag + , Ba 2+ , Cd 2+ , Cu 2+ , and Pb 2+ , share common binding sites with binding efficiencies varying in the sequence of Pb 2+ >Cu 2+ >Ag 2+ >Cd 2+ >Ba 2+ . The binding of Hg 2+ involved a different binding site with an increase in binding efficiency in the presence of Ag + . (orig.)

A 1.7 MeV tandem accelerator has been recently installed at Centro Atómico Bariloche, Argentina. This communication includes a brief description of the system facility with the main associated equipment, in particular that used for PIXE measurements. The X-ray detector efficiency was experimentally determined by comparing X-ray characteristic spectra with theoretical predictions. The knowledge of this parameter allows us to perform quantification without standards with good precision. We show some recent applications of PIXE in archaeology and forensic science done at our laboratory. In the archaeological field we determined elements constituent of pastes and black, white, brown and ocher pigments from Aguada Portezuelo Culture (600–900 AD). This study allowed us to infer about the presence of psilomelante mineral (a mineral with barium) as precursor of some black pigments. In the forensic field we determined trace elements that are present in seven gunpowders commonly used in Argentina. We note that any gunpowder can be distinguished by the presence of trace elements.

At first glance X-Ray fluorescence analysis seems to be a very sensitive and effectful method to detect element traces in the multielement mode. But in praxi the application range is restricted, if X-Ray tubes are used as excitation sources. To overcome this situation, it is necessary to improve the conditions of excitation and to reduce the background, produced by different scattering effects. TXRF, PIXE and SYXRF, which allow multielement analysis in the trace- and ultratrace region are using this strategy. In the case of TXRF a remarkable background reduction is achieved if the sample is prepared as a thin amorphous film on a planar sample holder and the excitation beam of a X-Ray tube is totally reflected on its surface. In the case of PIXE a particle beam of high intensity is used as excitation source, improving the conditions of excitation and giving the opportunity of spatial resolved analyses. In the case of SYXRF the X-Ray fraction of synchrotron radiation is used as excitation source, giving the opportunity, to improve the conditions of excitation as well as to reduce the background by using the high polarisation of the beam. In this case, too, spatial resolved analysis are possible. The principles of the three methods are described, their advantages and disadvantages are critically compared and advanced applications from different analytical fields are presented. (orig.)

Elemental composition of the steel of two ancient swords (Japanese and Damascus from a private collection) was characterized using in air IBA techniques. Our results contribute for the understanding the processes of manufacturing (hammering and quenching) and surface treatments applied in these swords. The Particle Induced X-ray Emission (PIXE) measurements along the Damascus blade allowed to identify and to trace a superficial concentration profile for the elements such Cr, Mn, Fe, Ni, Cu, Zn and As, while results for the Japanese blade showed only the presence of iron. The carbon content on the surface was also investigated using a resonant region in the Elastic Backscattering Spectrometry (EBS) measurements and the results have shown a slightly difference between the surfaces under investigation. In order to investigate the nitrogen content on surface, that could explain the hardening process, we used Nuclear Reaction Analysis (NRA) and the results shown that nitrogen content was under our detection limit for the technique (0.3% in mass). The measurements of PIXE, NRA and EBS were taken using the external beam setup installed at Lamfi – São Paulo/Brazil, the latter being successfully implemented for the first time in this facility.

Elemental composition of the steel of two ancient swords (Japanese and Damascus from a private collection) was characterized using in air IBA techniques. Our results contribute for the understanding the processes of manufacturing (hammering and quenching) and surface treatments applied in these swords. The Particle Induced X-ray Emission (PIXE) measurements along the Damascus blade allowed to identify and to trace a superficial concentration profile for the elements such Cr, Mn, Fe, Ni, Cu, Zn and As, while results for the Japanese blade showed only the presence of iron. The carbon content on the surface was also investigated using a resonant region in the Elastic Backscattering Spectrometry (EBS) measurements and the results have shown a slightly difference between the surfaces under investigation. In order to investigate the nitrogen content on surface, that could explain the hardening process, we used Nuclear Reaction Analysis (NRA) and the results shown that nitrogen content was under our detection limit for the technique (0.3% in mass). The measurements of PIXE, NRA and EBS were taken using the external beam setup installed at Lamfi - São Paulo/Brazil, the latter being successfully implemented for the first time in this facility.

Elemental composition of the steel of two ancient swords (Japanese and Damascus from a private collection) was characterized using in air IBA techniques. Our results contribute for the understanding the processes of manufacturing (hammering and quenching) and surface treatments applied in these swords. The Particle Induced X-ray Emission (PIXE) measurements along the Damascus blade allowed to identify and to trace a superficial concentration profile for the elements such Cr, Mn, Fe, Ni, Cu, Zn and As, while results for the Japanese blade showed only the presence of iron. The carbon content on the surface was also investigated using a resonant region in the Elastic Backscattering Spectrometry (EBS) measurements and the results have shown a slightly difference between the surfaces under investigation. In order to investigate the nitrogen content on surface, that could explain the hardening process, we used Nuclear Reaction Analysis (NRA) and the results shown that nitrogen content was under our detection limit for the technique (0.3% in mass). The measurements of PIXE, NRA and EBS were taken using the external beam setup installed at Lamfi – São Paulo/Brazil, the latter being successfully implemented for the first time in this facility

The LHCb Vertex Detector (VELO) will be upgraded in 2018 along with the other subsystems of LHCb in order to enable full detector readout at 40 MHz. LHCb will run without a hardware trigger and all data will be fed directly to the software triggering algorithms in the CPU farm. The upgraded VELO is a lightweight silicon hybrid pixel detector with 55 um square pixels, operating in vacuum in close proximity to the LHC beams. The readout will be provided by a dedicated front end ASIC, dubbed VeloPix, matched to the LHCb luminosity requirements. VeloPix is a binary pixel chip with a matrix of 256 x 256 pixels, covering an area of 2 cm^2. It is designed in a 130 nm CMOS technology, and is closely related to the Timepix3, from the Medipix family of ASICs. The principal challenge that the chip has to meet is a hit rate of up to 900 Mhits/s/ASIC, resulting in a data rate of more than 16 Gbit/s. Combining pixels into groups of 2x4 super-pixels enables the use of shared logic and a reduction of bandwidth due to combine...

Fundamental processes of plant physiology are affected or regulated by mineral nutrients. Hence understanding the mechanisms of nutrient uptake and their functions in plant metabolism is of fundamental importance in both basic and applied plant studies. The present knowledge of ion uptake mechanisms is based mostly on techniques for bulk analysis, including analysis of small (mg-sized) samples but without spatially resolved results. On the other hand, advanced studies of elemental transport at a cellular level are conducted using techniques with high and very high spatial resolution, but with low sensitivity for elemental analysis. Thus the results obtained are usually restricted to macronutrients or elements present in high quantities. There is a high demand for studies of the functions of trace elements. In addition, it is known that, depending on their concentrations, elements can play different roles in plant life. Studies related to elemental deficiency and toxicity, as well as environmental pollution, require accurate, fully quantitative methods with good spatial resolution. Ideally, these studies should be conducted on organs and tissues as far down as the cellular level. This is where micro-PIXE has been applied until present and can in the near future play a much more important role. Progress is subject to closer collaboration between plant biologists and the PIXE community in terms of addressing problems of specimen preparation, refinement of analytical protocols such as quantitative elemental mapping and the interpretation of results

Non-destructive analysis of precious art objects is an important tool to solve provenance problems or to facilitate restoration. External beam PIXE analysis is one of the most powerful and popular methods used in this respect. The paper summarises the external beam PIXE set-up at the Accelerator Laboratory in Budapest, and two selected applications are described. Different parts of a small Cambodian metal sculpture probably made in the 11th century were analysed. It was observed that the sculpture was composed of an iron core and an outer bronze shell. This sculptural technique was well known in the Middle-East but no indication has been found about its use in the Far-East, yet. Before its restoration paint traces on a wooden relief of St. Jerome made by an unknown artist in about 1600 were analysed. Different white and red paints were distinguished at selected points and the presence of titanium on a certain part of the relief was attributed to a repainting in modern times

Full text: The knowledge of the intracellular distribution of biological relevant metals is important to understand their mechanisms of action in cells, either for physiological, toxicological or pathological processes. However, the direct detection of trace metals in single cells is a challenging task that requires sophisticated analytical developments. The aim of this seminar will be to present the recent achievements in this field using micro-PIXE analysis. The combination of micro-PIXE with RBS (Rutherford Backscattering Spectrometry) and STIM (Scanning Transmission lon Microscopy) allows the quantitative determination of trace metal content within sub-cellular compartments. The application of STlM analysis will be more specifically highlighted as it provides high spatial resolution imaging (<200 nm) and excellent mass sensitivity (<0.1 ng). Application of the STIM-PIXE-RBS methodology is absolutely needed when organic mass loss appears during PIXE-RBS irradiation. This combination of STIM-PIXE-RBS provides fully quantitative determination of trace element content, expressed in μg/g, which is a quite unique capability for micro-PIXE compared to other micro-analytical methods such as the electron and synchrotron X-ray fluorescence or the techniques based on mass spectrometry. Examples of micro-PIXE studies for subcellular imaging of trace elements in the various fields of interest will be presented such as metal-based toxicology, pharmacology, and neuro degeneration [1] R. Ortega, G. Devés, A. Carmona. J. R. Soc. Interface, 6, (2009) S649-S658. (author)

Schizosaccharomyces pombe (S. pombe) is a eucaryotic cell type similar to mammalian cells but much more simple. As it also executes its cell cycle rapidly it is very useful for investigating basic processes in cells. In this paper we report a feasibility study of the applicability of microPIXE to investigate the interaction between S. pombe cells and the surrounding culture medium. Cells were cultured in various growth medium prior to preparation for analysis. 1 {mu}l drops of medium and cells were spotted onto polypropylene foils held in contact with a polished copper block previously cooled in liquid nitrogen. The samples were dehydrated by freeze-drying. Micro PIXE analysis was carried out with the IBC microbeam facility using a beam of 2.5 MeV protons focused to 1-2 {mu}m diameter. Initially no elemental contrast was observed between the cells and the medium, but by modifying the dilution of the cell suspension, the cells could be distinguished from the surrounding medium through an increased concentration of P and reduced concentration of Cl. The distribution of Na in the medium around the cells showed evidence of the action of the Na pump. Sporulation appears to be induced in the cells by adding Cu to the growth medium and the uptake of Cu by the cells could be clearly observed. This study shows that it is possible to analyse the mass transport of elements in and out of cells In the future this will enable concentration gradients to be analysed and allow the rate of production or consumption of individual cells to be calculated. By observing these patterns for individual cells (not populations) at various known points in the cell cycle, fundamental data can be derived.

Full Text Available Semi-terrestrial tardigrades are well-known for their tolerance to a variety of environmental extremes, including desiccation, freezing and radiation. Despite several attempts to reveal the genetic and molecular mechanisms behind the resilience of tardigrades, it is still unknown how these animals are able to maintain the integrity of their cellular components under severe stress. Quantitative or qualitative changes in molecular compounds (e.g., carbohydrates, proteins are expected, and have been the main line of research towards understanding the tolerance of tardigrades. In radiation tolerant bacteria, a tolerance mechanism based on manganese has been proposed. We evaluate this hypothesis in tardigrades and provide the first data on element composition in desiccated and non-desiccated specimens of two eutardigrade species, Richtersius coronifer and Milnesium cf. asiaticum. A focused 2 MeV proton microbeam was utilised to determine the elemental content, distributions and concentrations, using the ion beam analytical technique particle induced X-ray emission (PIXE. The presence of six elements – phosphorus, sulphur, chlorine, potassium, calcium and iron – were confirmed in all tardigrade specimens, at levels up to a few mg g–1. However, manganese was found in less than 10% of the analysed specimens, and in low amounts, thus our study provides no evidence for the manganese hypothesis. We also show that the distributions and/or concentrations of some elements differ between the two species as well as between the dehydrated and hydrated state. In particular, very low levels of iron were found in dehydrated M. cf. asiaticum. Our analysis shows that the PIXE technique is a useful tool for investigating questions on the distribution of elements both in dehydrated and hydrated tardigrades.

Schizosaccharomyces pombe (S. pombe) is a eucaryotic cell type similar to mammalian cells but much more simple. As it also executes its cell cycle rapidly it is very useful for investigating basic processes in cells. In this paper we report a feasibility study of the applicability of microPIXE to investigate the interaction between S. pombe cells and the surrounding culture medium. Cells were cultured in various growth medium prior to preparation for analysis. 1 μl drops of medium and cells were spotted onto polypropylene foils held in contact with a polished copper block previously cooled in liquid nitrogen. The samples were dehydrated by freeze-drying. Micro PIXE analysis was carried out with the IBC microbeam facility using a beam of 2.5 MeV protons focused to 1-2 μm diameter. Initially no elemental contrast was observed between the cells and the medium, but by modifying the dilution of the cell suspension, the cells could be distinguished from the surrounding medium through an increased concentration of P and reduced concentration of Cl. The distribution of Na in the medium around the cells showed evidence of the action of the Na pump. Sporulation appears to be induced in the cells by adding Cu to the growth medium and the uptake of Cu by the cells could be clearly observed. This study shows that it is possible to analyse the mass transport of elements in and out of cells In the future this will enable concentration gradients to be analysed and allow the rate of production or consumption of individual cells to be calculated. By observing these patterns for individual cells (not populations) at various known points in the cell cycle, fundamental data can be derived

Background: Zhejiang Province is an important producing area of proto-porcelain. Huoshaoshan kiln site in Deqing County is the only kiln known currently for firing proto-porcelain from the late Western Zhou Dynasty to the late Spring and Autumn Period. Also it is the earliest kiln site unearthed for only firing proto-porcelain so far. It is of great significance for the exploration of Chinese early celadon firing technology. Purpose: The aim is to disclose the elemental characteristics of these proto-porcelains and study the sources of the raw materials and relationship between these proto-porcelains. Methods: We selected 18 samples made at the early period (from the late Western Zhou Dynasty to the early Spring and Autumn Period), 15 samples made at the middle and last period (the last period of the middle Spring and Autumn Period), and 17 samples made at the last period (the last period of the late Spring and Autumn Period). Proton Induced X-ray Emission (PIXE) was used to analyze these samples and measure the chemical compositions of these proto-porcelains. The factor analysis is used to study the sources of the raw materials and relationship between these proto-porcelains made in the different periods. Results: The results show that for the raw materials of body and glaze, the proto-porcelains at the last period are different from those at the early period, while the same as those at the middle and last period. Conclusion: PIXE combining with factor analysis can be used to study effectively the sources of the raw materials and relationship between these proto-porcelains. (authors)

Leaves of Ni hyperaccumulator Berkheya coddii were chosen as a model to investigate the influence of eight freeze-substitution protocols on the Ni content and distribution. Freeze-substitution of leaf samples cryofixed by high-pressure freezing was carried out in dry acetone, methanol, diethyl ether and tetrahydrofuran. The same substitution media were also used with dimethylglyoxime added as a precipitation reagent. The samples were infiltrated and embedded in Spurr's resin. Micro-PIXE analysis of Ni concentration and localization, complemented by proton backscattering for matrix assessment, was performed using the nuclear microprobe at Materials Research Group, iThemba LABS, South Africa. True elemental maps and concentrations were obtained using GeoPIXE-II software. The results were compared with the control results obtained for the parallel air-dried samples, corrected for the water content. The highest Ni content was found in the leaf samples substituted in diethyl ether. This concentration was statistically different from the results obtained for other media. In case of diethyl ether medium Ni was mainly localized in the mesophyll tissue, and the distribution map of this element was in accordance with previous results obtained for freeze-dried and frozen-hydrated leaves of this species. The same distribution pattern was observed for specimens embedded in dry acetone, but Ni concentration was significantly lower. Tetrahydrofuran medium preserved Ni preferentially in the epidermis and vascular tissue, and the elemental map for samples embedded in this medium was distorted. Ni was almost completely washed out from samples substituted in methanol and it was thus impossible to obtain a picture of its distribution. Dimethylglyoxime did not improve the preservation of this element. These results show that diethyl ether is a suitable substitution medium for assessment of Ni concentration and distribution in leaves of B. coddii

The possibility of obtaing integral comparative data for particulate distribution in urban areas from PIXE analysis of tree leaves is discussed in relation to the leaf gross anatomy, to the diffusion of selected tree species in such areas and to the implementation of experimental techniques necessary to make PIXE analysis effective. Multielemental scans were performed on a small set samples; results are compared to PIXE analysis of typical urban aerosols. The validity of the method and the criteria for yearly relative comparisons of different areas are discissed

The principle of measurement of PIXE are explained. It has in comparison with SEM and EPM, the following characteristics such as; very short measurement and analysis time, developed detection sensitivity for more than 100 elements, no need of pretreatment, undestructive analysis method in the air, possibility of trace element analysis by using micro specimen and information input of chemical bonding condition. Bio-medical applications have been, the microanalysis of multi elements in light element matrix forming living body and the diagnosis of kidney cancer and other diseases. Environmental applications have been, detection of the composition of sea water and the detection of the pollutants of the rivers by elements concentration distribution. It is also applied for managing the amount of impurities in electronic materials and monitoring the emitted elements from fusion reactor. It is used for archaeological analysis such as, analysis of gold fixing in ancient Rome and earthernware analysis of ancient China. As for the chemical bonding condition, the small difference of chemical bonding has been able to be observed clearly as a difference of strength over the multiple spectra, and PIXE has prospects in multiple fields. 24 refs., 21 figs.

Regulations to control the huge amounts of sludge produced by wastewater are needed. Sludge generated in conventional sedimentators or anaerobic digesters were characterized by Proton Induced X-ray Emission (PIXE). It was possible to determine the presence of macro nutrient elements, such as P and K, and secondary nutrients like Ca, S, and Mg. Moreover, heavy elements like Cu, Zn, and Pb were also found. The sludge treatment in anaerobic digesters increased the amount of certain elements Al, Si, S, Cl, and K; decrease in Ca, Ti, and Cu, and no change in V, Cr, and Zn. Possible uses of this sludge are also suggested

Concerning the PIXE analysis of Cr(VI) in water using ion-exchange filters, the limit of detection (LOD) and the influence of matrix anions were investigated. In order to look for the experimental condition for obtaining the minimum LOD, we measured the Cr-Kα X-ray counts and background counts under the Kα X-ray peak as a function of the incident proton energy and the thickness of the Mylar absorber foil in front of the detector. To investigate the interference by coexisting anions, each of PO 4 3- , SO 4 2- , NO 3 - , Cl - , and F - ions and Cr(VI) ions were mixed in aqueous solutions and adsorbed on DE81-DEAE cellulose paper, a weakly basic anion exchanger with diethylaminoethyl functional groups. Then the filter samples were measured by PIXE using 2.5 MeV proton beams. We obtained a LOD of 0.16 μg or 8 ppb for 20 mL samples at a proton energy of 2.5 MeV and a Mylar film thickness of 50 or 100 μm. The experimental results on the mixed solutions indicated that NO 3 - , Cl - , and F - as coexisting ions didn't interfere significantly with determination of a 50 μg/L Cr(VI) concentration for 40 mL total solution volume, despite the total amount of anions was about 90% of ion exchange capacity of a filter. On the other hand, slight interferences by PO 4 3- ions were observed. However, under the same condition, we found that if the total amount of SO 4 2- ions was higher than 20% of ion exchange capacity, they induced significant interferences in determining Cr(VI). (author)

Full Text Available Endosomal sorting is an essential control mechanism for signaling through the epidermal growth factor receptor (EGFR. We report here that the guanine nucleotide exchange factor αPIX, which modulates the activity of Rho-GTPases, is a potent bimodal regulator of EGFR trafficking. αPIX interacts with the E3 ubiquitin ligase c-Cbl, an enzyme that attaches ubiquitin to EGFR, thereby labelling this tyrosine kinase receptor for lysosomal degradation. We show that EGF stimulation induces αPIX::c-Cbl complex formation. Simultaneously, αPIX and c-Cbl protein levels decrease, which depends on both αPIX binding to c-Cbl and c-Cbl ubiquitin ligase activity. Through interaction αPIX sequesters c-Cbl from EGFR and this results in reduced EGFR ubiquitination and decreased EGFR degradation upon EGF treatment. However, quantitatively more decisive for cellular EGFR distribution than impaired EGFR degradation is a strong stimulating effect of αPIX on EGFR recycling to the cell surface. This function depends on the GIT binding domain of αPIX but not on interaction with c-Cbl or αPIX exchange activity. In summary, our data demonstrate a previously unappreciated function of αPIX as a strong promoter of EGFR recycling. We suggest that the novel recycling regulator αPIX and the degradation factor c-Cbl closely cooperate in the regulation of EGFR trafficking: uncomplexed αPIX and c-Cbl mediate a positive and a negative feedback on EGFR signaling, respectively; αPIX::c-Cbl complex formation, however, results in mutual inhibition, which may reflect a stable condition in the homeostasis of EGF-induced signal flow.

Visible coloured traces on the surface of two selected wedge-shaped artefacts (pendants) of slate from the late Neolithic of South Scandinavia was analysed by means of proton-induced x-ray emission spectroscopy (PIXE). PIXE is shown to be a feasible tool in investigating surface layers of archeological significance. Three different gold-silver alloys was found on the two pendants. The results indicate that we shall have to reconsider the general accepted theories on the economic basis of the early Bronze Age in the area. (author)

The comparative analyses of AAS and PIXE (Proton-Induced X-ray Emission) show very good agreement in the absolute values of the concentrations of all metals analyzed. The practical detection limits are about 10 -10 g for the investigated element in both measuring processes, so that the analysis of pure air samples is possible with both methods. PIXE is particularly suitable for the analysis of aerosol samples as it is not necessary to process the filter, the samples are not destroyed, and many elements can be simultaneously analyzed within a short time (5-10 min.). Furthermore, the possibility of automatization enables an efficient treatment of meteorological problems. (orig.) [de

Diabetes mellitus, a metabolic disease characterized by high blood glucose levels (hyperglycemia) due to defects in insulin secretion, or action, or both, is a debilitating disease leading to other complications and death of many people in the world. Some of the medicinal plants implicated in the herbal recipes for the treatment of diabetes in Nigeria have been reported. Additional medicinal plants used for the treatment of diabetes in Nigeria are presented in this work. These medicinal plants are becoming increasingly important and relevant as herbal drugs due to their use as antioxidants, nutraceuticals, food additives and supplements in combating diabetes. Elemental compositions of these anti-diabetic medicinal plants were determined using PIXE technique. The 1.8 MV collimated proton beam from the 2.5 MV AN 2000 Van de Graaff accelerator at Istituto Nazionale di Fisica Nucleare (INFN), Laboratori Nazionali di Legnaro (LNL) Legnaro (Padova) Italy was employed for the work. The results show the detection of twenty-one elements which include Mg, P, Ca, K, Mn, Cu, Zn, S, Cr, Co, Ni and V that are implicated in the regulation of insulin and the control of the blood-sugar levels in the human body. The entire plant of Boerhavia diffusa, Securidaca longipedunculata stem, leaves of Peperomia pellucida, Macrosphyra longistyla, Olax subscorpioidea, Phyllanthus muerillanus, Jatropha gossypifolia, Cassia occidentalis, Phyllanthus amarus, and leaf and stem of Murraya koenigii, which have high concentrations of these elements could be recommended as vegetables, nutraceuticals, food additives, supplements and drugs in the control and management of diabetes, if toxicity profiles indicate that they are safe. However, significantly high contents of Al and Si in the entire plant of Bryophyllum pinnatum, and As, Cr, and Cu in Ocimum gratissimum leaf suggest that these plants should be avoided by diabetic patients to prevent complications.

Diabetes mellitus, a metabolic disease characterized by high blood glucose levels (hyperglycemia) due to defects in insulin secretion, or action, or both, is a debilitating disease leading to other complications and death of many people in the world. Some of the medicinal plants implicated in the herbal recipes for the treatment of diabetes in Nigeria have been reported. Additional medicinal plants used for the treatment of diabetes in Nigeria are presented in this work. These medicinal plants are becoming increasingly important and relevant as herbal drugs due to their use as antioxidants, nutraceuticals, food additives and supplements in combating diabetes. Elemental compositions of these anti-diabetic medicinal plants were determined using PIXE technique. The 1.8 MV collimated proton beam from the 2.5 MV AN 2000 Van de Graaff accelerator at Istituto Nazionale di Fisica Nucleare (INFN), Laboratori Nazionali di Legnaro (LNL) Legnaro (Padova) Italy was employed for the work. The results show the detection of twenty-one elements which include Mg, P, Ca, K, Mn, Cu, Zn, S, Cr, Co, Ni and V that are implicated in the regulation of insulin and the control of the blood-sugar levels in the human body. The entire plant of Boerhavia diffusa, Securidaca longipedunculata stem, leaves of Peperomia pellucida, Macrosphyra longistyla, Olax subscorpioidea, Phyllanthus muerillanus, Jatropha gossypifolia, Cassia occidentalis, Phyllanthus amarus, and leaf and stem of Murraya koenigii, which have high concentrations of these elements could be recommended as vegetables, nutraceuticals, food additives, supplements and drugs in the control and management of diabetes, if toxicity profiles indicate that they are safe. However, significantly high contents of Al and Si in the entire plant of Bryophyllum pinnatum, and As, Cr, and Cu in Ocimum gratissimum leaf suggest that these plants should be avoided by diabetic patients to prevent complications

The joint research on 'Application of micro-PIXE and imaging technology to life science' supported by the Inter-organizational Atomic Energy Research Program, had been performed for three years, from 2006FY to 2009FY. Aiming to apply in-air micro-PIXE analytical system to life science, the research was consisting of 7 collaborative themes related to beam engineering for micro-PIXE and applied technology of element mapping in biological/medical fields. The system, so-called micro-PIXE camera, to acquire spatial element mapping in living cells was originally developed by collaborative research between the JAEA and the department of engineering of Tohoku University. This review covers these research results. (author)

A thorough microscopic investigation by SR XRF and micro-PIXE brings insight into the probable techniques used in the manufacture of thirteen Dacian gold bracelets, one of the most spectacular archaeological finds ever on the territory of Romania.

A thorough microscopic investigation by SR XRF and micro-PIXE brings insight into the probable techniques used in the manufacture of thirteen Dacian gold bracelets, one of the most spectacular archaeological finds ever on the territory of Romania. (orig.)

Multielemental analyses of aerosol samples are widely used in air pollution receptor modelling. Specifically, the chemical mass balance (CMB) model has become a powerful tool in urban air quality studies. Input data required for the CMB includes not only the traditional X-ray fluorescence (and hence PIXE) detected elements, but also total mass, organic and inorganic carbon, and other light elements including Mg, Na and F. The circular streaker sampler, in combination with PIXE analysis, has developed into a powerful tool for obtaining time-resolved, multielemental aerosol data. However, application in CMB modelling has been limited by the absence of total mass and complementary light element data. This study reports on progress in using techniques complementary to PIXE to obtain additional data from circular streaker samples, maintaining the nondestructive, instrumental approach inherent in PIXE: Beta-gauging using a 147 Pm source for total mass; optical absorption for inorganic carbon; and PIGE to measure the lighter elements. (orig.)

The ePix100 x-ray camera is a new system designed and built at SLAC for experiments at the Linac Coherent Light Source (LCLS). The camera is the first member of a family of detectors built around a single hardware and software platform, supporting a variety of front-end chips. With a readout speed of 120 Hz, matching the LCLS repetition rate, a noise lower than 80 e-rms and pixels of 50 µm × 50 µm, this camera offers a viable alternative to fast readout, direct conversion, scientific CCDs in imaging mode. The detector, designed for applications such as X-ray Photon Correlation Spectroscopy (XPCS) and wavelength dispersive X-ray Emission Spectroscopy (XES) in the energy range from 2 to 10 keV and above, comprises up to 0.5 Mpixels in a very compact form factor. In this paper, we report the performance of the camera during its first use at LCLS.

Various foods come with varieties; each presents its own uniqueness in term of beneficial nutrients. Differentiation of these varieties will assist to obtain optimum benefit from their consumption, hence PIXE technique was used to differentiate known cowpea varieties in South-west Nigeria. Local names for the varieties were alayin nla, alayin wewe, mala, drum and sakata. The technique detected six major elements (Mg, K, Ca, P, S and CI) and several trace elements (AI, Fe, Ni, Cu, Mn, Sr, Si, Rb and Ti). The concentration of beneficial elements in the varieties differ and comparison with recommended daily allowance value shows consumption of some of the variety is sufficient. This research work will guide health workers in their recommendation of cowpea for nutritional deficiency.

Brownish bowl originating from an underwater shipwreck located near Belitung island in the Java Sea, some 600 km south-east from Singapore, has been measured with particle induced X-ray emission. This study was a pilot project for the - now a spin-off company - Recenart research team where one target was to evaluate the authenticity of the different type of art objects. PIXE measurements were done from three different material positions from a single bowl received from a customer. These locations were categorized as a bluish/greenish pigment (under glaze), thick glaze and the body clay. When the obtained data was compared to the other references from different dynasties and kiln sites, the closest match was indeed the Tang dynasty, Tongguan/Ghangsha kiln-site potsherds - from where the bowl in question was also suspected to originate.

Shanghai is the largest city in China, and it also has a very long history. Archaeologists have found that six thousand yeas ago, there were ancient people living at Songze, Qingpu County, Shanghai. This paper reports the study of ancient potteries unearthed from the Guangfulin site located at Songjiang, Shanghai. The potteries unearthed from Guangfulin site belonged to two different culture types: the Liangzhu culture type (local culture) and a new culture, which might be derived from elsewhere. PIXE has been used to measure the chemical compositions of samples and factor analysis was used. Experimental results show that the compositions of the pottery from the two phases are different from each other. It means that the raw materials used to make the ancient pottery originate from different places. This results support the idea suggested by archaeologists that a group of ancient people migrated to the Shanghai area from some other place 4000 years ago

The composition of inks in a group of 24 drawings of ten XVI century Italian painters, has been determined by PIXE at the external micro-beam line of the Centro de Micro Analisis de Materiales of the Universidad Autonoma de Madrid. Ink elemental thicknesses have been determined by comparison with a set of certified thin standards. A comprehensive comparison of inks has also been performed by renormalisation of spectra and definition of an ink-to-ink distance. The elemental compositions and the ink-to-ink distances give consistent results that are generally in line with the appearance of the drawings and add relevant instrumental information to the stylistic observation, revealing for example the presence of retouches and additions in different parts of a drawing. Cluster analysis performed on a subgroup of 13 artefacts from the Genoese painter Luca Cambiaso and his school has revealed a partition that separates neatly the work of the master from that of his followers

Availability of clean drinking water is an essential requirement for human health. The Ganga water is being widely used for drinking and irrigation purposes in many cities situated near the bank of the river, which effect the human health. Hence investigation of toxic elements of Ganga water is very important. PIXE (Particle Induce X-ray Emission) is well known and useful technique for finding out qualitative and quantitative analysis of various samples (taken from environment) and may contains about 30-50 elements together with concentration of about 1ppb. The elemental analysis depends on the inner-shell ionization process and measurement of the X-ray yield of the samples. For the present investigation, samples of Ganga water were collected from Varanasi and Allahabad

High Fe concentrations were reported from roots of plants grown in soil. This has been discussed as a possible Fe source for plants, since the concentrations shown in the roots were much higher than in the shoots. There are, however, also some indications that soil contamination at the root surface of soil grown plants could have led to an overestimation of the Fe concentration in roots. Fe distribution in root cross sections of barley (Hordeum vulgare L. cv. Alexis) has been studied to investigate this hypothesis. Micro-PIXE analyses in point and mapping mode were complemented by the STIM technique. Based on the correlation between Fe and soil-related elements (Ti, Al and Si), most of Fe located at the root surface could be attributed to soil contamination. It could also be shown that this soil contamination leads to an overestimation of Fe concentration in roots. (author)

A content of various elements in the hair of milking cows changed with relation between health condition and nutritious condition within an extent of normal physiological situation. Each element content in the hair of normal and healthy milking cow was analyzed by particle induced X-ray emission (PIXE) analysis. A physiological change of the element content was cleared in the hairs of milking cow, although it was not cleared in a different nutritious conditions. Cupper and Strontium contents in the milking cow were changed physiologically with the number of delivery times, the number of days after delivery, a quantity of fat correction milk (FCM) and a body weight. Selenium content in fin-luster hairs of the milking cow was plenty significantly, in comparison with the one in the other hairs. (M. Suetake)

We report a methodology used to analyze suspended marine particulates by particle induced X-ray emission (PIXE). Water samples from an estuary in Brazil were filtered soon after collection onto pre-weighed Nuclepore filters, washed with deionized water, dried to constant weight and analyzed as thin targets. Because of the relatively high mass loadings (0.1-1.0 mg/cm 2 ) on the filters, proton bombardment times of a few minutes were adequate for maintaining good counting statistics. Precision and accuary were determined by replicate analysis and intercomparison to geochemical standards. Suspensions of standards in deionized water were filtered dried, weighed and analyzed in a similar fashion as our samples of marine particulates. Net X-ray intensities were related to mass by calibration against pure elemental standards. Initial experiments showed systematically low concentrations for all elements determined by PIXE relative to known values. Further experiments verified that this systematic errors was due to an uneven distribution of mass on the surface of the filters. Improvements in the filtration technique have eliminated the topographic effect on our samples and the PIXE resultes were substantially improved. Variations in matrix and particle size of the samples analyzed did not cause any measureable analytical effect. PIXE thus seems well suited for providing rapid, multi-element data on samples of marine particulates if suitable precautions are made during the sample preparation process. (orig.)

The potential of using dried algae as a novel preconcentration technique for the analysis of water samples by PIXE was examined. The algae cells were found to contain significant levels of P and S, indicative of phosphorous- and sulfur-containing groups on the cell wall or inside the algae cells which may serve as potential binding sites for metal ions. When C. vulgaris was used on mixed metal solutions, linear responses were observed for Ag{sup +}, Ba{sup 2+}, and Cd{sup 2+} in the concentration range from 10 ng/g to 1 {mu}g/g; for Cu{sup 2+} and Pb{sup 2+} from 10 ng/g to 5 {mu}g/g; and for Hg{sup 2+} from 10 ng/g to 10 {mu}g/g. When S. bacillaris was used, linear responses were observed from 10 ng/g up to 10 {mu}g/g for all of the metal cations investigated. The PIXE results demonstrated that metal binding at low concentrations involves replacement of sodium on the cell wall and that at high concentrations magnesium was also replaced. Competitive binding studies indicate that the metal ions, Ag{sup +}, Ba{sup 2+}, Cd{sup 2+}, Cu{sup 2+}, and Pb{sup 2+}, share common binding sites with binding efficiencies varying in the sequence of Pb{sup 2+}>Cu{sup 2+}>Ag{sup 2+}>Cd{sup 2+}>Ba{sup 2+}. The binding of Hg{sup 2+} involved a different binding site with an increase in binding efficiency in the presence of Ag{sup +}. (orig.).

In oxygen evolving photosynthetic organisms, light is absorbed and its energy used for the conversion of chemical products in two photosystems: PSI and PSII. Each photosystem is composed of a protein core which binds a pigment antenna and a Reaction Center (RC). RC of PSI is considered an "Iron-Sulfur" type. There are six components that participate in the charge separation after light absorption occurs in PSI: the center chlorophyll P700, two acceptors A 0 and A 1 and three FeS centers F X, F A and F B. However, the exact number of polypeptides, their exact molecular weight, their relative abundances and the active components associated to those polypeptides remain still to be completely characterized. In particular the FeS centers have been difficult to detect in a direct way in a gel band, because the amount of centers involved is under the detection limits of the conventional techniques. This study has been under-taken to explore the capability of particle induced X-ray emission (PIXE) to detect in a qualitative way the presence of Fe in some of the protein bands obtained by Sodium Dodecyl Sulfate Polyacrylamide Gel Electrophoresis (SDS-PAGE) from the PSI complex. The complex was isolated from membranes of thermophilic cyanobacteria: Synechochoccus sp. The polyacrylamide gel electrophoresis of the complex shows eight subunits of 66, 60-65, 14, 13, 9, 8 and 7 KDa. In-air PIXE was performed at 2 MeV and proved to be an adequate tool for direct identification of the iron present in the gel bands.

An artificial neural network (ANN) has been trained with real-sample PIXE (particle X-ray induced emission) spectra of organic substances. Following the training stage ANN was applied to a subset of similar samples thus obtaining the elemental concentrations in muscle, liver and gills of Cyprinus carpio. Concentrations obtained with the ANN method are in full agreement with results from one standard analytical procedure, showing the high potentiality of ANN in PIXE quantitative analyses

An artificial neural network (ANN) has been trained with real-sample PIXE (particle X-ray induced emission) spectra of organic substances. Following the training stage ANN was applied to a subset of similar samples thus obtaining the elemental concentrations in muscle, liver and gills of Cyprinus carpio. Concentrations obtained with the ANN method are in full agreement with results from one standard analytical procedure, showing the high potentiality of ANN in PIXE quantitative analyses.

In order to confirm accuracy of the direct analysis of filter samples containing atmospheric aerosol particles collected on a polycarbonate membrane filter by PIXE, we carried out PIXE analysis on a National Institute of Standards and Technology (NIST, USA) air particulate on filter media (SRM 2783). For 16 elements with NIST certified values determined by PIXE analysis - Na, Mg, Al, Si, S, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn and Pb - quantitative values were 80-110% relative to NIST certified values except for Na, Al, Si and Ni. Quantitative values of Na, Al and Si were 140-170% relative to NIST certified values, which were all high, and Ni was 64%. One possible reason why the quantitative values of Na, Al and Si were higher than the NIST certified values could be the difference in the X-ray spectrum analysis method used. (author)

In view of the importance of the X-ray production cross-section for the determination of element concentration in a given material, we have measured them experimentally for light elements Sc and Fe using proton beams of energy between 40 and 180 keV. The obtained K X-ray production cross-section is compared with the previous experimental results. The experimental K X-ray production cross-section for proton induced X-ray emission (PIXE) analysis, using low energy (200 keV) accelerator, have been improved

Thermoluminescence (TL) dating and Proton Induced X-ray Emission (PIXE) techniques have been utilized for the study of archaeological pottery fragment samples from Tell Saka Site, which is located at 25 km south east of Damascus city, Syria. Four samples were chosen randomly from the site, two from third level and two from fourth level for dating using TL technique and the results were in good agreement with the date assigned by archaeologists. Twenty-eight sherds were analyzed using PIXE technique in order to identify and characterize the elemental composition of pottery excavated from third and fourth levels, using 3 MV tandem accelerator in Damascus. The analysis provided almost 20 elements (Na, Mg, Al, Si, P, S, K, Ca, Ti, Mn, Fe, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb). However, only 14 elements as follows: K, Ca, Ti, Mn, Fe, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb were chosen for statistical analysis and have been processed using two multivariate statistical methods, Cluster and Factor analysis. The studied pottery were classify into two well defined groups. (author)

As part of an ongoing evaluation of its suitability for atmospheric biomonitoring, bark from olive trees (Olea europaea Linn.) has been collected and searched for trace elements by means of two nuclear-analytical techniques--instrumental neutron activation analysis (INAA) and proton-induced X-ray emission (PIXE). The sampling for the present study was carried out across two separate sections of an established grid for air-quality surveys in mainland Portugal. The dual location comprises 58 collection sites--littoral-north (29 sites) and littoral-centre (29 sites). Both techniques are intrinsically accurate and may be seen to complement each other in the way that, as a whole, they yield 46 elements, with an overlap of 16 elements. Among the latter, this paper focuses on four of them and looks into their joint determination. Descriptive statistics for soil-related Al and Ti, and for sea-related Cl and Br, show results for each element to be fairly comparable. The degree of association between elemental patterns by either technique, as seen through nonparametric tests (Kendall's R K ), is outstanding. No statistical evidence (Wilcoxon's T) for relative bias in correlated samples--consistently higher or lower results by one technique--could be found as well. As far as this study goes, INAA and PIXE may be used interchangeably for determining the present elements in olive-tree bark

We developed a PIXE analysis system which provides spatial distribution images of elements in a region of 3x3 cm 2 with a spatial resolution of ∼0.5 mm. We call this system a submilli-PIXE camera. For in-vivo imaging of plants, we combined the submilli-PIXE camera with an in-air analysis. The high-speed beam scanning and the in-air analysis also reduce the risk of damaging the plants, thus in-vivo imaging could be realized. We applied the in-air submilli-PIXE camera to phytoremediation research. Phytoremediation is a technology for cleaning metal-contaminated soils using plant physiology. To study accumulation mechanisms for heavy metals, elemental distribution in plant organ should be known as well as average concentration. Elemental images of fronds were obtained in-vivo without sample preparation. Elemental map of the fronds showed that arsenic was accumulated in the edges of Pteris vittata fronds. The in-air submilli-PIXE camera clearly shows the accumulation of arsenic in fronds. The in-air submilli-PIXE camera is an effective tool for undertaking phytoremediation research. (author)

Highlights: {yields} PIXE was found to give the same results for trace elements in glass as ICP. {yields} PIXE can non-destructively determine trace element concentrations in auto glass. {yields} Measured Ca, Fe, Ti, Mn, and Sr in auto glass with PIXE. -- Abstract: The elemental concentrations of five trace elements in tempered sheet glass fragments were determined using particle-induced X-ray emission (PIXE) spectrometry. The trace element concentrations for calcium, iron, manganese, strontium, and titanium are compared to those obtained by inductively-coupled plasma-atomic emission spectrometry (ICP-AES) following complete digestion by hydrofluoric acid. For these five elements, the absolute concentrations obtained by both methods are shown to agree well over a wide range of concentrations. The limits of detection for trace elements are typically lower for the ICP-AES method. However, we show that the concentrations of these five elements can be accurately measured by the PIXE method. Since PIXE is an entirely non-destructive method, there exists a niche for this technique to be used as a complement to the more sensitive ICP-AES technique in the forensic analysis of sheet glass.

Elemental composition fingerprinting by PIXE technique is very attractive for obsidian provenance studies as it may proceed in a non-destructive mode, even if a more complete elemental characterization can be obtained by ICP-MS and/or ICP-AES. Only few studies have compared results obtained by both methods for solid rock samples. In this work, elemental compositions were determined by ICP-MS/-AES for international geochemical standards and by ICP-MS/-AES and PIXE for inter-laboratory reference obsidians. In addition 49 obsidian source samples and artefacts were analysed by both ICP-MS/-AES and PIXE. Instrumental work and measurement quality control performed for obsidian chemical characterization, underline that PIXE and ICP-MS/-AES provide reproducible, accurate and comparable measurements. In some volcanic districts the limited number of elements dosed by PIXE is sufficient for the discrimination of the potential raw sources of obsidians. Therefore, PIXE can be an advantageous substitute to ICP-MS/-AES techniques for provenance studies

The elemental composition of Fe rich rocks used as pigment during prehistoric periods can provide valuable information about the type of material used and their geological origin. However, these materials present several analytical constraints since their patrimonial value involve using non-invasive techniques maintaining a high sensitivity of the detection and the quantification of trace elements. Micro-beam techniques also require to take into account the heterogeneity of these geomaterials from the macroscopic to microscopic scales. Several previous studies have demonstrated that PIXE analysis satisfies these analytical conditions. However, application of micro-PIXE analysis is still complex when thin and discontinuous layer of pigment is deposed on the surface of other materials such as rocks or bones. In such case, PIXE imaging could improve the ability to take into account the high heterogeneity of such archaeological objects. In study, we used PIXE imaging system developed at the NewAGLAE facility in order to visualize distribution of elements associated with iron-rich pigment phase. The results obtained show that PIXE maps can improve the identification of the main trace elements specific to the iron mineral phase. By grouping pixels of iron-rich areas and performing quantitative treatment, it was possible to reveal additional trace elements associated to pigment. This study highlights the contribution of PIXE imaging to the identification of elements associated with mineral phases of interest and to use them as proxies to discriminate different geological materials used in archaeological context.

The use of fluoride for the prevention of caries is based on the transformation of hydroxylapatite to fluoroapatite in the presence of fluoride ions, thereby strengthening tooth structure. Adhesion of dentin and resin composite (tooth-colored restoration material) requires a dentin bonding system, since resin composite is not able to adhere to dentin directly. Demineralization of dentin by acid etching is an important step in the dentin bonding system, however, demineralization also introduces weaknesses in tooth structure. If the demineralized dentin could be strengthened by the application of fluoride, then the dentin-resin composite bond strength might also improve. To test this hypothesis, the present study evaluated the influence of fluoride applications on the strength of the dentin-resin composite bond by (1) tensile strength testing analyses, (2) SEM analyses of tooth structure, and (3) detection of calcium (Ca) and fluorine (F) distribution patterns by micro proton-induced X-ray emission (μ-PIXE) and micro proton-induced gamma-ray emission (μ-PIGE) analyses conducted at the Takasaki Ion Accelerators for Advanced Radiation Application (TIARA) at the Takasaki Advanced Radiation Research Institute (TARRI). In this study, the dentin in extracted human molars was exposed by grinding and the dentin was etched with 35% phosphoric acid. Fluoride was applied at two concentrations, 0.022% (100 ppm F) and 2.21% (10,000 ppm F) NaF solution, for two time periods, 30 and 60 s, prior to bonding the resin composite with the treated dentin. Controls were prepared in the same manner, but without the fluoride application. Bond strength was measured with a micro-tensile testing unit, and the fluorine and calcium distributions at the interface between dentin and resin composite were detected by μ-PIGE and μ-PIXE analysis, respectively. Results indicate that the 10,000 ppm F applications resulted in higher bond strengths than observed in either the 100 ppm F applications or

The use of fluoride for the prevention of caries is based on the transformation of hydroxylapatite to fluoroapatite in the presence of fluoride ions, thereby strengthening tooth structure. Adhesion of dentin and resin composite (tooth-colored restoration material) requires a dentin bonding system, since resin composite is not able to adhere to dentin directly. Demineralization of dentin by acid etching is an important step in the dentin bonding system, however, demineralization also introduces weaknesses in tooth structure. If the demineralized dentin could be strengthened by the application of fluoride, then the dentin-resin composite bond strength might also improve. To test this hypothesis, the present study evaluated the influence of fluoride applications on the strength of the dentin-resin composite bond by (1) tensile strength testing analyses, (2) SEM analyses of tooth structure, and (3) detection of calcium (Ca) and fluorine (F) distribution patterns by micro proton-induced X-ray emission (μ-PIXE) and micro proton-induced gamma-ray emission (μ-PIGE) analyses conducted at the Takasaki Ion Accelerators for Advanced Radiation Application (TIARA) at the Takasaki Advanced Radiation Research Institute (TARRI). In this study, the dentin in extracted human molars was exposed by grinding and the dentin was etched with 35% phosphoric acid. Fluoride was applied at two concentrations, 0.022% (100 ppm F) and 2.21% (10,000 ppm F) NaF solution, for two time periods, 30 and 60 s, prior to bonding the resin composite with the treated dentin. Controls were prepared in the same manner, but without the fluoride application. Bond strength was measured with a micro-tensile testing unit, and the fluorine and calcium distributions at the interface between dentin and resin composite were detected by μ-PIGE and μ-PIXE analysis, respectively. Results indicate that the 10,000 ppm F applications resulted in higher bond strengths than observed in either the 100 ppm F applications or

The use of fluoride for the prevention of caries is based on the transformation of hydroxylapatite to fluoroapatite in the presence of fluoride ions, thereby strengthening tooth structure. Adhesion of dentin and resin composite (tooth-colored restoration material) requires a dentin bonding system, since resin composite is not able to adhere to dentin directly. Demineralization of dentin by acid etching is an important step in the dentin bonding system, however, demineralization also introduces weaknesses in tooth structure. If the demineralized dentin could be strengthened by the application of fluoride, then the dentin-resin composite bond strength might also improve. To test this hypothesis, the present study evaluated the influence of fluoride applications on the strength of the dentin-resin composite bond by (1) tensile strength testing analyses, (2) SEM analyses of tooth structure, and (3) detection of calcium (Ca) and fluorine (F) distribution patterns by micro proton-induced X-ray emission ({mu}-PIXE) and micro proton-induced gamma-ray emission ({mu}-PIGE) analyses conducted at the Takasaki Ion Accelerators for Advanced Radiation Application (TIARA) at the Takasaki Advanced Radiation Research Institute (TARRI). In this study, the dentin in extracted human molars was exposed by grinding and the dentin was etched with 35% phosphoric acid. Fluoride was applied at two concentrations, 0.022% (100 ppm F) and 2.21% (10,000 ppm F) NaF solution, for two time periods, 30 and 60 s, prior to bonding the resin composite with the treated dentin. Controls were prepared in the same manner, but without the fluoride application. Bond strength was measured with a micro-tensile testing unit, and the fluorine and calcium distributions at the interface between dentin and resin composite were detected by {mu}-PIGE and {mu}-PIXE analysis, respectively. Results indicate that the 10,000 ppm F applications resulted in higher bond strengths than observed in either the 100 ppm F

The content of metals of the asphaltenes obtained from the KU-46 mexican crude with n-heptane was evaluated. The found metals in higher concentration are transition metals as well as the vanadium, nickel, copper and zinc. Moreover the sulfur in high concentrations was quantified. The metallic content of the asphaltenes revealed that the crude contains a lower quantity of metals unlike the vacuum residue previously analysed. (Author)

Ideal radiotherapy deposits a large amount of energy in the tumour volume, and none in the surrounding healthy tissues. Proton therapy comes closer to this goal because of a greater concentration of dose, well defined proton ranges and points of energy release which are precisely known - the Bragg peak1. In the past, the development of clinical proton therapy has been hampered by complexity, size, and cost. To be clinically effective, energies of several hundred MeV are required; these were previously unavailable for hospital installations, and pioneering institutions had to work with complex, inadequate equipment originally intended for nuclear physics research. Recently a number of specialist organizations and commercial companies have been working on dedicated systems for proton therapy. One, IBA of Belgium, has equipment for inhouse hospital operation which encompasses a complete therapy centre, delivered as a turnkey package and incorporating a compact, automated, higher energy cyclotron with isocentric gantries. Their system will be installed at Massachusetts General Hospital, Boston. The proton therapy system comprises: - a 235 MeV isochronous cyclotron to deliver beams of up to 1.5 microamps, but with a hardware limitation to restrict the maximum possible dose; - variable energy beam (235 to 70 MeV ) with energy spread and emittance verification; - a beam transport and switching system to connect the exit of the energy selection system to the entrances of a number of gantries and fixed beamlines. Along the beam transport system, the beam characteristics are monitored with non-interceptive multiwire ionization chambers for automatic tuning; - gantries fitted with nozzles and beamline elements for beam control; both beam scattering and beam wobbling techniques are available for shaping the beam;

We present here an global study of the interaction between high- energy particles and heavy nuclei, an interaction which holds obvious interest in relation to the problems of nuclear fragmentation and which, up lo now has only been studied piecemeal. We have used three stacks of photographic emulsions which were irradiated by 13.8 GeV/c protons, 17 GeV/c negative pions and 24 GeV/c protons. All three irradiations took place in a 180 K.G. magnetic field using CERN beams. (Author) 20 refs.

We present here an global study of the interaction between high- energy particles and heavy nuclei, an interaction which holds obvious interest in relation to the problems of nuclear fragmentation and which, up lo now has only been studied piecemeal. We have used three stacks of photographic emulsions which were irradiated by 13.8 GeV/c protons, 17 GeV/c negative pions and 24 GeV/c protons. All three irradiations took place in a 180 K.G. magnetic field using CERN beams. (Author) 20 refs.